RE: High commit size
Do not use mmap/auto on Windows, standard access mode only. In cassandra.yaml: disk_access_mode: standard Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Visit us at Dmexco: Hall: 7, Aisle: A, Stand: 030 September 12-13 Cologne, Germany [dmexco] http://www.dmexco.de/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Rene Kochen [mailto:rene.koc...@emea.schange.com] Sent: Monday, September 10, 2012 14:47 To: user@cassandra.apache.org Subject: Re: High commit size The problem is that the system just freezes and nodes are dying. The system becomes very unresponsive and it always happens when the shareable amount of RAM reaches the total number of bytes in the system. Is there something in Windows that I can tune in order to avoid this behavior? I cannot easily migrate to Linux right now. Thanks, Rene 2012/9/10 Oleg Dulin oleg.du...@gmail.commailto:oleg.du...@gmail.com It is memory-mapped I/O. I wouldn't worry about it. BTW, Windows might not be the best choice to run Cassandra on. My experience running Cassandra on Windows has not been positive one. We no longer support Windows as our production platform. Regards, Oleg On 2012-09-10 09:00:02 +, Rene Kochen said: Hi all, On my test cluster I have three Windows Server 2008 R2 machines running Cassandra 1.0.11 If i use memory mapped IO (the default), then the nodes freeze after a while. Paging is disabled. The private bytes are OK (8GB). That is the amount I use in the -Xms and -Xmx arguments. The virtual size is big as expected because of the memory mapped IO. However, the working set size (size in RAM) is 24 GB (my total RAM usage). If I look with Process Explorer to the physical memory section I see a very high value in the WS Sharable section. Anyone has a clue what is going om here? Many thanks! Rene image -- Regards, Oleg Dulin NYC Java Big Data Engineer http://www.olegdulin.com/ inline: signature-logoc64.pnginline: dmexco-logofa6.png
RE: High commit size
We used Cassandra on Windows for more than a year in production for RTB and other staff, that requires lowest possible latency. We used mmap before issues like yours, switched to mmap index only and finally to standard. No big difference in performance, standard was most stable. The huge difference is to run C* on Linux instead of Windows. Migration was pretty easy. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Visit us at Dmexco: Hall: 7, Aisle: A, Stand: 030 September 12-13 Cologne, Germany [dmexco] http://www.dmexco.de/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Rene Kochen [mailto:rene.koc...@emea.schange.com] Sent: Monday, September 10, 2012 17:03 To: user@cassandra.apache.org Subject: Re: High commit size For performance reasons I switched to memory mapped IO. Is there a way to make memory-mapped IO work in Windows? Thanks! 2012/9/10 Viktor Jevdokimov viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Do not use mmap/auto on Windows, standard access mode only. In cassandra.yaml: disk_access_mode: standard Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063tel:%2B370%205%20212%203063, Fax +370 5 261 0453tel:%2B370%205%20261%200453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News]http://www.adform.com Visit us at Dmexco: Hall: 7, Aisle: A, Stand: 030 September 12-13 Cologne, Germany [dmexco]http://www.dmexco.de/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Rene Kochen [mailto:rene.koc...@emea.schange.commailto:rene.koc...@emea.schange.com] Sent: Monday, September 10, 2012 14:47 To: user@cassandra.apache.orgmailto:user@cassandra.apache.org Subject: Re: High commit size The problem is that the system just freezes and nodes are dying. The system becomes very unresponsive and it always happens when the shareable amount of RAM reaches the total number of bytes in the system. Is there something in Windows that I can tune in order to avoid this behavior? I cannot easily migrate to Linux right now. Thanks, Rene 2012/9/10 Oleg Dulin oleg.du...@gmail.commailto:oleg.du...@gmail.com It is memory-mapped I/O. I wouldn't worry about it. BTW, Windows might not be the best choice to run Cassandra on. My experience running Cassandra on Windows has not been positive one. We no longer support Windows as our production platform. Regards, Oleg On 2012-09-10 09:00:02 +, Rene Kochen said: Hi all, On my test cluster I have three Windows Server 2008 R2 machines running Cassandra 1.0.11 If i use memory mapped IO (the default), then the nodes freeze after a while. Paging is disabled. The private bytes are OK (8GB). That is the amount I use in the -Xms and -Xmx arguments. The virtual size is big as expected because of the memory mapped IO. However, the working set size (size in RAM) is 24 GB (my total RAM usage). If I look with Process Explorer to the physical memory section I see a very high value in the WS Sharable section. Anyone has a clue what is going om here? Many thanks! Rene image -- Regards, Oleg Dulin NYC Java Big Data Engineer http://www.olegdulin.com/ inline: image001.pnginline: image002.pnginline: signature-logo5395.pnginline: dmexco-logo634e.png
RE: Persistent connection among nodes to communicate and redirect request
9160 is a client port. Nodes are using messaging service on storage_port (7000) for intra-node communication. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. -Original Message- From: Niteesh kumar [mailto:nitees...@directi.com] Sent: Tuesday, October 02, 2012 12:32 To: user@cassandra.apache.org Subject: Persistent connection among nodes to communicate and redirect request while looking at netstat table i observed that my cluster nodes not using persistent connection to talk among themselves on port 9160 to redirect request. I also observed that local write latency is around 30-40 microsecond, while its takes around .5 miliseconds if the chosen node is not the node responsible for the key for 50K QPS. I think this attributes to connection making time among servers as my servers are on same rack. how can i configure my servers to use persistent connection on port 9160 thus exclude connection making time for each request that is redirected...
RE: Persistent connection among nodes to communicate and redirect request
Never seen connections between nodes on 9160 port, 7000 only. From the source code, for example, thrift request goes to rpc port 9160 (org.apache.cassandra.thrift.CassandraDaemon, org.apache.cassandra.thrift.CassandraServer), then to StorageProxy (org.apache.cassandra.service.StorageProxy), which forward request (if needed) to other endpoints via MessagingService (org.apache.cassandra.net.MessagingService), which uses storage_port from yaml, not a thrift port (rpc_port in yaml). What else could be wrong? Wiki or source code? Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. -Original Message- From: rohit bhatia [mailto:rohit2...@gmail.com] Sent: Tuesday, October 02, 2012 14:35 To: user@cassandra.apache.org Subject: Re: Persistent connection among nodes to communicate and redirect request i guess 7000 is only for gossip protocol. Cassandra still uses 9160 for RPC even among nodes Also, I see Connections over port 9160 among various cassandra Nodes in my cluster. Please correct me if i am wrong.. PS: mentioned Here http://wiki.apache.org/cassandra/CloudConfig On Tue, Oct 2, 2012 at 4:56 PM, Viktor Jevdokimov viktor.jevdoki...@adform.com wrote: 9160 is a client port. Nodes are using messaging service on storage_port (7000) for intra-node communication. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. -Original Message- From: Niteesh kumar [mailto:nitees...@directi.com] Sent: Tuesday, October 02, 2012 12:32 To: user@cassandra.apache.org Subject: Persistent connection among nodes to communicate and redirect request while looking at netstat table i observed that my cluster nodes not using persistent connection to talk among themselves on port 9160 to redirect request. I also observed that local write latency is around 30-40 microsecond, while its takes around .5 miliseconds if the chosen node is not the node responsible for the key for 50K QPS. I think this attributes to connection making time among servers as my servers are on same rack. how can i configure my servers to use persistent connection on port 9160 thus exclude connection making time for each request that is redirected...
RE: unbalanced ring
To run, or not to run? All this depends on use case. There're no problems running major compactions (we do it nightly) in one case, there could be problems in another. Just need to understand, how everything works. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Mobile: +370 650 19588, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Visit us at IAB RTB workshop October 11, 4 pm in Sala Rossa [iab forum] http://www.iabforum.it/iab-forum-milano-2012/agenda/11-ottobre/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Alain RODRIGUEZ [mailto:arodr...@gmail.com] Sent: Thursday, October 11, 2012 09:17 To: user@cassandra.apache.org Subject: Re: unbalanced ring Tamar be carefull. Datastax doesn't recommand major compactions in production environnement. If I got it right, performing major compaction will convert all your SSTables into a big one, improving substantially your reads performence, at least for a while... The problem is that will disable minor compactions too (because of the difference of size between this SSTable and the new ones, if I remeber well). So your reads performance will decrease until your others SSTable reach the size of this big one you've created or until you run an other major compaction, transforming them into a maintenance normal process like repair is. But, knowing that, I still don't know if we both (Tamar and I) shouldn't run it anyway (In my case it will greatly decrease the size of my data 133 GB - 35GB and maybe load the cluster evenly...) Alain 2012/10/10 B. Todd Burruss bto...@gmail.commailto:bto...@gmail.com it should not have any other impact except increased usage of system resources. and i suppose, cleanup would not have an affect (over normal compaction) if all nodes contain the same data On Wed, Oct 10, 2012 at 12:12 PM, Tamar Fraenkel ta...@tok-media.commailto:ta...@tok-media.com wrote: Hi! Apart from being heavy load (the compact), will it have other effects? Also, will cleanup help if I have replication factor = number of nodes? Thanks Tamar Fraenkel Senior Software Engineer, TOK Media [Inline image 1] ta...@tok-media.commailto:ta...@tok-media.com Tel: +972 2 6409736 Mob: +972 54 8356490 Fax: +972 2 5612956 On Wed, Oct 10, 2012 at 6:12 PM, B. Todd Burruss bto...@gmail.commailto:bto...@gmail.com wrote: major compaction in production is fine, however it is a heavy operation on the node and will take I/O and some CPU. the only time i have seen this happen is when i have changed the tokens in the ring, like nodetool movetoken. cassandra does not auto-delete data that it doesn't use anymore just in case you want to move the tokens again or otherwise undo. try nodetool cleanup On Wed, Oct 10, 2012 at 2:01 AM, Alain RODRIGUEZ arodr...@gmail.commailto:arodr...@gmail.com wrote: Hi, Same thing here: 2 nodes, RF = 2. RCL = 1, WCL = 1. Like Tamar I never ran a major compaction and repair once a week each node. 10.59.21.241eu-west 1b Up Normal 133.02 GB 50.00% 0 10.58.83.109eu-west 1b Up Normal 98.12 GB50.00% 85070591730234615865843651857942052864 What phenomena could explain the result above ? By the way, I have copy the data and import it in a one node dev cluster. There I have run a major compaction and the size of my data has been significantly reduced (to about 32 GB instead of 133 GB). How is that possible ? Do you think that if I run major compaction in both nodes it will balance the load evenly ? Should I run major compaction in production ? 2012/10/10 Tamar Fraenkel ta...@tok-media.commailto:ta...@tok-media.com Hi! I am re-posting this, now that I have more data and still unbalanced ring: 3 nodes, RF=3, RCL=WCL=QUORUM Address DC RackStatus State LoadOwns Token 113427455640312821154458202477256070485 x.x.x.xus-east 1c Up Normal 24.02 GB33.33% 0 y.y.y.y us-east 1c Up Normal 33.45 GB33.33% 56713727820156410577229101238628035242 z.z.z.zus-east 1c Up Normal 29.85 GB33.33
RE: what is more important (RAM vs Cores)
IMO, in most cases you'll be limited by the RAM first. Take into account size of sstables, you will need to keep bloom filters and indexes in RAM and if it will not fit, 4 cores, or 24 cores doesn't matter, except you're on SSD. You need to design first, stress test second, conclude last. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. -Original Message- From: Hagos, A.S. [mailto:a.s.ha...@tue.nl] Sent: Friday, October 12, 2012 12:17 To: user@cassandra.apache.org Subject: RE: what is more important (RAM vs Cores) Hi there, My application is uses Cassandra to store abstracted sensor data from a sensor network in large building (up to 3000 sensors). For now I am starting one node in one floor of the building, for the future it will definitely be a cluster. Some of the sensors have up 16HZ sampling rate. And now I want to make a decision if I have to focus on big RAM or large number of cores. greetings Ambes From: Romain HARDOUIN [romain.hardo...@urssaf.fr] Sent: Friday, October 12, 2012 10:57 AM To: user@cassandra.apache.org Subject: Re: what is more important (RAM vs Cores) Hi, Sure it depends... but IMHO 6 GB is suboptimal for big data because it means 1,5 GB or 2 GB for Cassandra. Maybe you could elaborate your use case. You really want a one node cluster ? cheers, Romain wang liang wla...@gmail.com a écrit sur 12/10/2012 10:36:15 : Hi, Hagos, I think it depends on your business case. Big RAM reduce latency and improve responsibility, High number of cores increase concurrency of your app. thanks. On Fri, Oct 12, 2012 at 4:23 PM, Hagos, A.S. a.s.ha...@tue.nl wrote: Hi All, For of my projects I want to buy a machine to host Casssandra database. The options I am offered are machines with 16GB RAM with Quad-Core processor and 6GB RAM with Hexa-Core processor. Which one do you recommend, big RAM or high number of cores? greetings Ambes -- Best wishes, Helping others is to help myself.
RE: Super columns and arrays
struct SuperColumn {
1: required binary name,
2: required listColumn columns,
}
Best regards / Pagarbiai
Viktor Jevdokimov
Senior Developer
Email: viktor.jevdoki...@adform.com
Phone: +370 5 212 3063
Fax: +370 5 261 0453
J. Jasinskio 16C,
LT-01112 Vilnius,
Lithuania
Disclaimer: The information contained in this message and attachments is
intended solely for the attention and use of the named addressee and may be
confidential. If you are not the intended recipient, you are reminded that the
information remains the property of the sender. You must not use, disclose,
distribute, copy, print or rely on this e-mail. If you have received this
message in error, please contact the sender immediately and irrevocably delete
this message and any copies. -Original Message-
From: Thierry Templier [mailto:thierry.templ...@restlet.com]
Sent: Friday, October 12, 2012 13:44
To: user@cassandra.apache.org
Subject: Super columns and arrays
Hello,
I wonder if it's possible to specify an array of values as a value of a super
column... If it's not possible, is there another way to do that?
Thanks very much for your help.
Thierry
RE: Cassandra nodes failing with OOM
We've seen OOM in a situation, when OS was not properly prepared in production. http://www.datastax.com/docs/1.1/install/recommended_settings Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider Take a ride with Adform's Rich Media Suitehttp://vimeo.com/adform/richmedia [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: some.unique.lo...@gmail.com [mailto:some.unique.lo...@gmail.com] On Behalf Of Ивaн Cобoлeв Sent: Saturday, November 17, 2012 08:08 To: user@cassandra.apache.org Subject: Cassandra nodes failing with OOM Dear Community, advice from you needed. We have a cluster, 1/6 nodes of which died for various reasons(3 had OOM message). Nodes died in groups of 3, 1, 2. No adjacent died, though we use SimpleSnitch. Version: 1.1.6 Hardware: 12Gb RAM / 8 cores(virtual) Data: 40Gb/node Nodes: 36 nodes Keyspaces:2(RF=3, R=W=2) + 1(OpsCenter) CFs:36, 2 indexes Partitioner: Random Compaction: Leveled(we don't want 2x space for housekeeping) Caching: Keys only All is pretty much standard apart from the one CF receiving writes in 64K chunks and having sstable_size_in_mb=100. No JNA installed - this is to be fixed soon. Checking sysstat/sar I can see 80-90% CPU idle, no anomalies in io and the only change - network activity spiking. All the nodes before dying had the following on logs: INFO [ScheduledTasks:1] 2012-11-15 21:35:05,512 StatusLogger.java (line 72) MemtablePostFlusher 1 4 0 INFO [ScheduledTasks:1] 2012-11-15 21:35:13,540 StatusLogger.java (line 72) FlushWriter 1 3 0 INFO [ScheduledTasks:1] 2012-11-15 21:36:32,162 StatusLogger.java (line 72) HintedHandoff 1 6 0 INFO [ScheduledTasks:1] 2012-11-15 21:36:32,162 StatusLogger.java (line 77) CompactionManager 5 9 GCInspector warnings were there too, they went from ~0.8 to 3Gb heap in 5-10mins. So, could you please give me a hint on: 1. How much GCInspector warnings per hour are considered 'normal'? 2. What should be the next thing to check? 3. What are the possible failure reasons and how to prevent those? Thank you very much in advance, Ivan inline: signature-logo49d2.png
RE: cassandra vs couchbase benchmark
Pure marketing comparing apples to oranges. Was Cassandra usage optimized? - What consistency level was used? (fastest reads with ONE) - Does Cassandra client used was token aware? (make request to appropriate node) - Was dynamic snitch turned off? (prevent forward request to other replica if can be processed locally) - Does Cassandra data model was used to mimic Couchbase data model? (Couchbase has only 1 value for 1 row) - What caching was used on Cassandra? (Couchbase uses memcache built-in) For our use case we've seen much better results upon testing from single node. Throughput grows almost linearly adding nodes and growing amount of data to the same level as for single node. Single node stats: - A column family with 30 GiB compressed data per node (100 GiB uncompressed) - 1 row with 10-30 columns weighted 0.5-2 KiB uncompressed - 1 node with 6 cores 24 GiB RAM, 8 GiB heap, 1600 MiB new heap - key cache only, 2M keys - random reads 70%, random writes 30% - Read latencies 10ms AVE100 with CPU 95%, 50k reads/s - Read latencies 5ms AVE100 with CPU 60%, 20k reads/s In reality, with many column families with different amount of data, read/write rates, performance results may significantly vary. Just need to know what and how to optimize for Cassandra to get best results. Couchbase is not for our use case because of its data model (requires reads for updates/inserts), so we can't compare it to Cassandra. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. -Original Message- From: Radim Kolar [mailto:h...@filez.com] Sent: Tuesday, December 11, 2012 17:42 To: user@cassandra.apache.org Subject: cassandra vs couchbase benchmark http://www.slideshare.net/Couchbase/benchmarking-couchbase#btnNext
RE: Partition maintenance
No way to read the taped data with TTL later - will disappear from tapes :) Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider Take a ride with Adform's Rich Media Suitehttp://vimeo.com/adform/richmedia [Adform News] http://www.adform.com [Adform awarded the Best Employer 2012] http://www.adform.com/site/blog/adform/adform-takes-top-spot-in-best-employer-survey/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Keith Wright [mailto:kwri...@nanigans.com] Sent: Tuesday, December 18, 2012 18:33 To: user@cassandra.apache.org Subject: Re: Partition maintenance My understanding was that TTLs only apply to columns and not on a per row basis. This means that for each column insert you would need to set that TTL. Does this mean that the amount of data space used in such a case would be the TTL * the number of columns? I was hoping there was a way to set a row TTL. See older post: http://comments.gmane.org/gmane.comp.db.cassandra.user/12701 From: Christopher Keller cnkel...@gmail.commailto:cnkel...@gmail.com Reply-To: user@cassandra.apache.orgmailto:user@cassandra.apache.org user@cassandra.apache.orgmailto:user@cassandra.apache.org Date: Tuesday, December 18, 2012 11:16 AM To: user@cassandra.apache.orgmailto:user@cassandra.apache.org user@cassandra.apache.orgmailto:user@cassandra.apache.org Subject: Re: Partition maintenance If I'm understanding you correctly, you can write TTL's on each insert. 18 months would be roughly 540 days which would be 46656000 seconds. I've not tried that number, but I use smaller TTL's all the time and they work fine. Once they are expired they get tombstones and are no longer searchable. Space is reclaimed as with any tombstone. --Chris On Dec 18, 2012, at 11:08 AM, stephen.m.thomp...@wellsfargo.commailto:stephen.m.thomp...@wellsfargo.com wrote: Hi folks. Still working through the details of building out a Cassandra solution and I have an interesting requirement that I'm not sure how to implement in Cassandra: In our current Oracle world, we have the data for this system partitioned by month, and each month the data that are now 18-months old are archived to tape/cold storage and then the partition for that month is dropped. Is there a way to do something similar with Cassandra without destroying our overall performance? Thanks in advance, Steve -- The downside of being better than everyone else is that people tend to assume you're pretentious. inline: signature-logo29.pnginline: signature-best-employer-logo4823.png
RE: LCS not removing rows with all TTL expired columns
@Bryan, To keep data size as low as possible with TTL columns we still use STCS and nightly major compactions. Experience with LCS was not successful in our case, data size keeps too high along with amount of compactions. IMO, before 1.2, LCS was good for CFs without TTL or high delete rate. I have not tested 1.2 LCS behavior, we're still on 1.0.x Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider Take a ride with Adform's Rich Media Suitehttp://vimeo.com/adform/richmedia [Adform News] http://www.adform.com [Adform awarded the Best Employer 2012] http://www.adform.com/site/blog/adform/adform-takes-top-spot-in-best-employer-survey/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: aaron morton [mailto:aa...@thelastpickle.com] Sent: Thursday, January 17, 2013 06:24 To: user@cassandra.apache.org Subject: Re: LCS not removing rows with all TTL expired columns Minor compaction (with Size Tiered) will only purge tombstones if all fragments of a row are contained in the SSTables being compacted. So if you have a long lived row, that is present in many size tiers, the columns will not be purged. (thus compacted compacted) 3 days after all columns for that row had expired Tombstones have to get on disk, even if you set the gc_grace_seconds to 0. If not they do not get a chance to delete previous versions of the column which already exist on disk. So when the compaction ran your ExpiringColumn was turned into a DeletedColumn and placed on disk. I would expect the next round of compaction to remove these columns. There is a new feature in 1.2 that may help you here. It will do a special compaction of individual sstables when they have a certain proportion of dead columns https://issues.apache.org/jira/browse/CASSANDRA-3442 Also interested to know if LCS helps. Cheers - Aaron Morton Freelance Cassandra Developer New Zealand @aaronmorton http://www.thelastpickle.com On 17/01/2013, at 2:55 PM, Bryan Talbot btal...@aeriagames.commailto:btal...@aeriagames.com wrote: According to the timestamps (see original post) the SSTable was written (thus compacted compacted) 3 days after all columns for that row had expired and 6 days after the row was created; yet all columns are still showing up in the SSTable. Note that the column shows now rows when a get for that key is run so that's working correctly, but the data is lugged around far longer than it should be -- maybe forever. -Bryan On Wed, Jan 16, 2013 at 5:44 PM, Andrey Ilinykh ailin...@gmail.commailto:ailin...@gmail.com wrote: To get column removed you have to meet two requirements 1. column should be expired 2. after that CF gets compacted I guess your expired columns are propagated to high tier CF, which gets compacted rarely. So, you have to wait when high tier CF gets compacted. Andrey On Wed, Jan 16, 2013 at 11:39 AM, Bryan Talbot btal...@aeriagames.commailto:btal...@aeriagames.com wrote: On cassandra 1.1.5 with a write heavy workload, we're having problems getting rows to be compacted away (removed) even though all columns have expired TTL. We've tried size tiered and now leveled and are seeing the same symptom: the data stays around essentially forever. Currently we write all columns with a TTL of 72 hours (259200 seconds) and expect to add 10 GB of data to this CF per day per node. Each node currently has 73 GB for the affected CF and shows no indications that old rows will be removed on their own. Why aren't rows being removed? Below is some data from a sample row which should have been removed several days ago but is still around even though it has been involved in numerous compactions since being expired. $ ./bin/nodetool -h localhost getsstables metrics request_summary 459fb460-5ace-11e2-9b92-11d67b6163b4 /virtual/cassandra/data/data/metrics/request_summary/metrics-request_summary-he-386179-Data.db $ ls -alF /virtual/cassandra/data/data/metrics/request_summary/metrics-request_summary-he-386179-Data.db -rw-rw-r-- 1 sandra sandra 5252320 Jan 16 08:42 /virtual/cassandra/data/data/metrics/request_summary/metrics-request_summary-he-386179-Data.db $ ./bin/sstable2json /virtual/cassandra/data/data/metrics/request_summary/metrics-request_summary-he-386179-Data.db -k $(echo -n 459fb460-5ace-11e2-9b92
RE: Concurrent write performance
Do you experience any performance problems? This will be the last thing to look at. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider Take a ride with Adform's Rich Media Suitehttp://vimeo.com/adform/richmedia [Adform News] http://www.adform.com [Adform awarded the Best Employer 2012] http://www.adform.com/site/blog/adform/adform-takes-top-spot-in-best-employer-survey/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Jay Svc [mailto:jaytechg...@gmail.com] Sent: Monday, January 21, 2013 17:28 To: user@cassandra.apache.org Subject: Concurrent write performance Folks, I would like to write(insert or update) to a single row in a column family. I have concurrent requests which will write to a single row. Do we see any performance implications because of concurrent writes to a single row where comparator has to sort the columns at the same time? Please share your thoughts. Thanks, Jay inline: signature-logo7f56.pnginline: signature-best-employer-logo42f0.png
RE: High Read and write through put
For such a generic question without technical details of requirements, the answer - use defaults. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider Take a ride with Adform's Rich Media Suitehttp://vimeo.com/adform/richmedia [Adform News] http://www.adform.com [Adform awarded the Best Employer 2012] http://www.adform.com/site/blog/adform/adform-takes-top-spot-in-best-employer-survey/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Jay Svc [mailto:jaytechg...@gmail.com] Sent: Monday, January 21, 2013 17:31 To: user@cassandra.apache.org Subject: High Read and write through put Folks, For given situation I am expecting multiple read and write request to a same cluster. What are primary design or configuration consideration we should make? Any thoughts or links to such documentation is appreciated. Thanks, Jay inline: signature-logo7f53.pnginline: signature-best-employer-logo18f3.png
RE: JMX CF Beans
src/java/org/apache/цassandra/db/DataTracker.java:
public double getBloomFilterFalseRatio()
{
…
return (double) falseCount / (trueCount + falseCount);
…
}
ReadCount/WriteCount on CF is for this CF on this node only, so it’s
local/internal only reads/writes for the node’s range.
Best regards / Pagarbiai
Viktor Jevdokimov
Senior Developer
Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com
Phone: +370 5 212 3063, Fax +370 5 261 0453
J. Jasinskio 16C, LT-01112 Vilnius, Lithuania
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Disclaimer: The information contained in this message and attachments is
intended solely for the attention and use of the named addressee and may be
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message in error, please contact the sender immediately and irrevocably delete
this message and any copies.
From: Nicolas Lalevée [mailto:nicolas.lale...@hibnet.org]
Sent: Friday, January 25, 2013 16:08
To: user@cassandra.apache.org
Subject: JMX CF Beans
Just a quick question about the attributes exposed via JMX. I have some doc [1]
but it doesn't help about CF beans.
The BloomFilterFalseRatio, is that the ratio of found vs missed, or the ratio
of false positive vs the number of tests, or something else ?
The ReadCount and WriteCount, how do they count regarding the replication
factor ? As far as I understand, the read and write on the StorageProxy is the
actual number of requests coming from clients. So judging that the sum on all
cf of the read and write is near equal to the replication factor multiply by
the number of read and write on the StorageProxy, I am guessing that the read
and write per cf are the replicas one. Am I right ?
Nicolas
[1] http://wiki.apache.org/cassandra/JmxInterface
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RE: data not shown up after some time
Are you sure your app is setting TTL correctly? TTL is in seconds. For 90 days it have to be 90*24*60*60=7776000. What If you set by accident 777600 (10 times less) - that will be 9 days, almost what you see. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider Take a ride with Adform's Rich Media Suitehttp://vimeo.com/adform/richmedia [Adform News] http://www.adform.com [Adform awarded the Best Employer 2012] http://www.adform.com/site/blog/adform/adform-takes-top-spot-in-best-employer-survey/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Matthias Zeilinger [mailto:matthias.zeilin...@bwinparty.com] Sent: Monday, January 28, 2013 15:57 To: user@cassandra.apache.org Subject: data not shown up after some time Hi, I´m a simple operations guy and new to Cassandra. I have the problem that one of our application is writing data into Cassandra (but not deleting them, because we should have a 90 days TTL). The application operates in 1 KS with 5 CF. my current setup: 3 node cluster and KS has a RF of 3 (I know it´s not the best setup) I can see now the problem that after 10 days most (nearly all) data are not showing anymore in the cli and also our application cannot see the data. I assume that it has something to do with the gc_grace_seconds, it is set to 10 days. I have read many documentations about tombstones, but our application doesn´t perform deletes. How can I see in the cli, if I row key has any tombstone or not. Could it be that there are some ghost tombstones? Thx for your help Br, Matthias Zeilinger Production Operation - Shared Services P: +43 (0) 50 858-31185 M: +43 (0) 664 85-34459 E: matthias.zeilin...@bwinparty.commailto:matthias.zeilin...@bwinparty.com bwin.party services (Austria) GmbH Marxergasse 1B A-1030 Vienna www.bwinparty.comhttp://www.bwinparty.com inline: signature-logo4c86.pnginline: signature-best-employer-logo4d95.png
RE: Why do Datastax docs recommend Java 6?
I would prefer Oracle to own an Azul's Zing JVM over any other (GC) to provide it for free for anyone :) Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider Take a ride with Adform's Rich Media Suitehttp://vimeo.com/adform/richmedia [Adform News] http://www.adform.com [Adform awarded the Best Employer 2012] http://www.adform.com/site/blog/adform/adform-takes-top-spot-in-best-employer-survey/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: jef...@gmail.com [mailto:jef...@gmail.com] Sent: Wednesday, February 06, 2013 02:23 To: user@cassandra.apache.org Subject: Re: Why do Datastax docs recommend Java 6? Oracle now owns the sun hotspot team, which is inarguably the highest powered java vm team in the world. Its still really the epicenter of all java vm development. Sent from my Verizon Wireless BlackBerry From: Ilya Grebnov i...@metricshub.commailto:i...@metricshub.com Date: Tue, 5 Feb 2013 14:09:33 -0800 To: user@cassandra.apache.orgmailto:user@cassandra.apache.org ReplyTo: user@cassandra.apache.orgmailto:user@cassandra.apache.org Subject: RE: Why do Datastax docs recommend Java 6? Also, what is particular reason to use Oracle JDK over Open JDK? Sorry, I could not find this information online. Thanks, Ilya From: Michael Kjellman [mailto:mkjell...@barracuda.com] Sent: Tuesday, February 05, 2013 7:29 AM To: user@cassandra.apache.orgmailto:user@cassandra.apache.org Subject: Re: Why do Datastax docs recommend Java 6? There have been tons of threads/convos on this. In the early days of Java 7 it was pretty unstable and there was pretty much no convincing reason to use Java 7 over Java 6. Now that Java 7 has stabilized and Java 6 is EOL it's a reasonable decision to use Java 7 and we do it in production with no issues to speak of. That being said there was one potential situation we've seen as a community where bootstrapping new node was using 3x more CPU and getting significantly less throughput. However, reproducing this consistently never happened AFAIK. I think until more people use Java 7 in production and prove it doesn't cause any additional bugs/performance issues Datastax will update their docs. Until now I'd say it's a safe bet to use Java 7 with Vanilla C* 1.2.1. I hope this helps! Best, Michael From: Baron Schwartz ba...@xaprb.commailto:ba...@xaprb.com Reply-To: user@cassandra.apache.orgmailto:user@cassandra.apache.org user@cassandra.apache.orgmailto:user@cassandra.apache.org Date: Tuesday, February 5, 2013 7:21 AM To: user@cassandra.apache.orgmailto:user@cassandra.apache.org user@cassandra.apache.orgmailto:user@cassandra.apache.org Subject: Why do Datastax docs recommend Java 6? The Datastax docs repeatedly say (e.g. http://www.datastax.com/docs/1.2/install/install_jre) that Java 7 is not recommended, but they don't say why. It would be helpful to know this. Does anyone know? The same documentation is referenced from the Cassandra wiki, for example, http://wiki.apache.org/cassandra/GettingStarted - Baron inline: signature-logo18be.pnginline: signature-best-employer-logo6784.png
RE: Testing compaction strategies on a single production server?
Just turn off dynamic snitch on survey node and make read requests from it directly with CL.ONE, watch histograms, compare. Regarding switching compaction strategy there're a lot of info already. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider Take a ride with Adform's Rich Media Suitehttp://vimeo.com/adform/richmedia [Adform News] http://www.adform.com [Adform awarded the Best Employer 2012] http://www.adform.com/site/blog/adform/adform-takes-top-spot-in-best-employer-survey/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Henrik Schröder [mailto:skro...@gmail.com] Sent: Tuesday, February 19, 2013 15:57 To: user Subject: Testing compaction strategies on a single production server? Hey, Version 1.1 of Cassandra introduced live traffic sampling, which allows you to measure the performance of a node without it really joining the cluster: http://www.datastax.com/dev/blog/whats-new-in-cassandra-1-1-live-traffic-sampling That page mentions that you can change the compaction strategy through jmx if you want to test out a different strategy on your survey node. That's great, but it doesn't give you a complete view of how your performance would change, since you're not doing reads from the survey node. But what would happen if you used jmx to change the compaction strategy of a column family on a single *production* node? Would that be a safe way to test it out or are there side-effects of doing that live? And if you do that, would running a major compaction transform the entire column family to the new format? Finally, if the test was a success, how do you proceed from there? Just change the schema? /Henrik inline: signature-logo18be.pnginline: signature-best-employer-logo6784.png
RE: Using Cassandra for read operations
Bill de hÓra already answered, I'd like to add: To achieve ~4ms reads (from client standpoint): 1. You can't use multi-slice, since different keys may occur on different nodes that require internode communication. Design you data and reads to use one key/row. 2. Use ConsistencyLevel.ONE to avoid waiting for other nodes. 3. Use smart client that selects endpoints by token (key) to put request to appropriate node, Astyanax (Java) or write such client yourself. 4. Turn off dynamic snitch. While coordinator node may read locally, dynamic snitch may redirect it to another replica. 5. Use SSD's to avoid re-cache issue when sstables are compacted. 6. If you do writes, the rest issue is GC. If you're not on Azul Zing JVM, which I can't confirm to be better than Oracle HotSpot or JRockit (both has GC issues), you can't tune JVM to avoid Young Gen GC pauses to be as low as you need. You will fight pause frequency VS time. So if you can afford Zing, check also Aerospike (ex-CitrusLeaf) alternative to Cassandra, which is written in C and has no GC issues. From: Bill de hÓra [mailto:b...@dehora.net] Sent: Thursday, February 21, 2013 22:07 To: user@cassandra.apache.org Subject: Re: Using Cassandra for read operations In a nutshell - - Start with defaults and tune based on small discrete adjustments and leave time to see the effect of each change. No-one will know your workload better than you and the questions you are asking are workload sensitive. - Allow time for tuning and spending time understanding the memory model and JVM GC. - Be very careful with caches. Leave enough room in the OS for its own disk cache. - Get an SSD Bill On 21 Feb 2013, at 19:03, amulya rattan talk2amu...@gmail.com wrote: Dear All, We are currently evaluating Cassandra for an application involving strict SLAs(Service level agreements). We just need one column family with a long key and approximately 70-80 bytes row. We are not concerned about write performance but are primarily concerned about read. For our SLAs, a read of max 15-20 rows at once(using multi slice), should not take more than 4 ms. Till now, on a single node setup, using cassandra' stress tool, the numbers are promising. But I am guessing that's because there is no network latency involved there and since we set memtable around 2gb(4 gb heap), we never had to get to Disk I/O. Assuming our nodes having 32GB RAM, a couple of questions regarding read: * To avoid disk I/Os, the best option we thought is to have data in memory. Is it a good idea to have memtable setup around 1/2 or 3/4 of heap size? Obviously flushing will take a lot of time but would that hurt that node's performance big time? * Cassandra stress tool only gives out average read latency. Is there a way to figure out max read-latency for a bunch of read operations? * How big a row cache can one have? Given that cassandra provides off- heap row caching, in a machine 32 gb RAM, would it be wise to have a 10 gb row cache with 8 gb java heap? And how big should the corresponding key cache be then? Any response is appreciated. ~Amulya Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.
RE: cannot start Cassandra on Windows7
You NEED to edit cassandra.yaml and log4j-server.properties paths before starting on Windows. There're a LOT of things to learn for starters. Google for Cassandra on Windows. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. -Original Message- From: Marina [mailto:ppi...@yahoo.com] Sent: Friday, March 22, 2013 17:21 To: user@cassandra.apache.org Subject: cannot start Cassandra on Windows7 Hi, I have downloaded apache-cassandra-1.2.3-bin.tar.gz and un-zipped it on my Windows7 machine (I did not find a Windows-specific distributable...). Then, I tried to start Cassandra as following and got an error: C:\Marina\Tools\apache-cassandra-1.2.3\bincassandra.bat -f Starting Cassandra Server Exception in thread main java.lang.ExceptionInInitializerError Caused by: java.lang.RuntimeException: Couldn't figure out log4j configuration: log4j-server.properties at org.apache.cassandra.service.CassandraDaemon.initLog4j(CassandraDaemo n.java:81) at org.apache.cassandra.service.CassandraDaemon.clinit(CassandraDaemon .java:57) Could not find the main class: org.apache.cassandra.service.CassandraDaemon. Pr ogram will exit. C:\Marina\Tools\apache-cassandra-1.2.3\bin It looks similar to the Cassandra issue that was already fixed: https://issues.apache.org/jira/browse/CASSANDRA-2383 however I am still getting this error I am an Administrator on my machine, and have access to all files in the apache- cassandra-1.2.3\conf dir, including the log4j ones. Do I need to configure anything else on Winows ? I did not find any Windows- specific installation/setup/startup instructions - if there are such documents somewhere, please let me know! Thanks, Marina
sstableloader throughput
Hi, We're using Casandra 1.0.12 sstableloader to import data from dedicated machine located in DC1 into the cluster of 32 nodes (RF=4), 16 nodes in DC1 and 16 nodes in DC2. To disable throttle for sstableloader we set in casasndra.yaml: stream_throughput_outbound_megabits_per_sec: 0 Outgoing network throughput is about 1Gbit, file copy from dedicated sstableloader machine throughput is 90MB/s into DC1 node and 50MB/s into DC2 node. But with sstableloader outgoing network traffic is only 9MB/s, importing 1 sstable of 480MB into cluster (~60MB/node) takes 8-9 minutes. Even with 50MB/s import should take less than a minute. Why sstableloader throughput is so low/slow? Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider Take a ride with Adform's Rich Media Suitehttp://vimeo.com/adform/richmedia [Adform News] http://www.adform.com [Adform awarded the Best Employer 2012] http://www.adform.com/site/blog/adform/adform-takes-top-spot-in-best-employer-survey/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. inline: signature-logo4489.pnginline: signature-best-employer-logoc08.png
RE: sstableloader throughput
Found https://issues.apache.org/jira/browse/CASSANDRA-3668 Weird. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider Take a ride with Adform's Rich Media Suitehttp://vimeo.com/adform/richmedia [Adform News] http://www.adform.com [Adform awarded the Best Employer 2012] http://www.adform.com/site/blog/adform/adform-takes-top-spot-in-best-employer-survey/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Viktor Jevdokimov [mailto:viktor.jevdoki...@adform.com] Sent: Wednesday, April 10, 2013 11:12 To: user@cassandra.apache.org Subject: sstableloader throughput Hi, We're using Casandra 1.0.12 sstableloader to import data from dedicated machine located in DC1 into the cluster of 32 nodes (RF=4), 16 nodes in DC1 and 16 nodes in DC2. To disable throttle for sstableloader we set in casasndra.yaml: stream_throughput_outbound_megabits_per_sec: 0 Outgoing network throughput is about 1Gbit, file copy from dedicated sstableloader machine throughput is 90MB/s into DC1 node and 50MB/s into DC2 node. But with sstableloader outgoing network traffic is only 9MB/s, importing 1 sstable of 480MB into cluster (~60MB/node) takes 8-9 minutes. Even with 50MB/s import should take less than a minute. Why sstableloader throughput is so low/slow? Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider Take a ride with Adform's Rich Media Suitehttp://vimeo.com/adform/richmedia [Adform News]http://www.adform.com [Adform awarded the Best Employer 2012]http://www.adform.com/site/blog/adform/adform-takes-top-spot-in-best-employer-survey/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. inline: image001.pnginline: image002.pnginline: signature-logo56e1.pnginline: signature-best-employer-logo63d8.png
RE: sstableloader throughput
Rsync is not for our case. Is sstableloader for 1.2.x faster? From: Edward Capriolo [mailto:edlinuxg...@gmail.com] Sent: Wednesday, April 10, 2013 15:52 To: user@cassandra.apache.org Subject: Re: sstableloader throughput Stables loader was slow in 1:0:x I had better luck with rsync. It was not fixed in the 1.0.x series. On Wednesday, April 10, 2013, Viktor Jevdokimov viktor.jevdoki...@adform.com wrote: Found https://issues.apache.org/jira/browse/CASSANDRA-3668 Weird. Hi, We're using Casandra 1.0.12 sstableloader to import data from dedicated machine located in DC1 into the cluster of 32 nodes (RF=4), 16 nodes in DC1 and 16 nodes in DC2. To disable throttle for sstableloader we set in casasndra.yaml: stream_throughput_outbound_megabits_per_sec: 0 Outgoing network throughput is about 1Gbit, file copy from dedicated sstableloader machine throughput is 90MB/s into DC1 node and 50MB/s into DC2 node. But with sstableloader outgoing network traffic is only 9MB/s, importing 1 sstable of 480MB into cluster (~60MB/node) takes 8-9 minutes. Even with 50MB/s import should take less than a minute. Why sstableloader throughput is so low/slow? Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.
RE: sstableloader throughput
Thanks, that could help to consider migration of the cluster to a newer version. We'll check the difference. From: Edward Capriolo [mailto:edlinuxg...@gmail.com] Sent: Wednesday, April 10, 2013 18:03 To: user@cassandra.apache.org Subject: Re: sstableloader throughput Yes. I did confirm that the 1.1 sstable loader works much better then the 1.0 version. The changes were not easy to backport to the 1.0.X branch so it did not happen. It is likely that 1.2 is even better :) On Wed, Apr 10, 2013 at 10:38 AM, Viktor Jevdokimov viktor.jevdoki...@adform.com wrote: Rsync is not for our case. Is sstableloader for 1.2.x faster? From: Edward Capriolo [mailto:edlinuxg...@gmail.com] Sent: Wednesday, April 10, 2013 15:52 To: user@cassandra.apache.org Subject: Re: sstableloader throughput Stables loader was slow in 1:0:x I had better luck with rsync. It was not fixed in the 1.0.x series. On Wednesday, April 10, 2013, Viktor Jevdokimov viktor.jevdoki...@adform.com wrote: Found https://issues.apache.org/jira/browse/CASSANDRA-3668 Weird. Hi, We're using Casandra 1.0.12 sstableloader to import data from dedicated machine located in DC1 into the cluster of 32 nodes (RF=4), 16 nodes in DC1 and 16 nodes in DC2. To disable throttle for sstableloader we set in casasndra.yaml: stream_throughput_outbound_megabits_per_sec: 0 Outgoing network throughput is about 1Gbit, file copy from dedicated sstableloader machine throughput is 90MB/s into DC1 node and 50MB/s into DC2 node. But with sstableloader outgoing network traffic is only 9MB/s, importing 1 sstable of 480MB into cluster (~60MB/node) takes 8-9 minutes. Even with 50MB/s import should take less than a minute. Why sstableloader throughput is so low/slow? Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.
RE: Does Memtable resides in Heap?
Memtables resides in heap, write rate impacts GC, more writes - more frequent and longer ParNew GC pauses. From: Jay Svc [mailto:jaytechg...@gmail.com] Sent: Friday, April 12, 2013 01:03 To: user@cassandra.apache.org Subject: Does Memtable resides in Heap? Hi Team, I have got this 8GB of RAM out of that 4GB allocated to Java Heap. My question is the size of Memtable does it contribute to heap size? or they are part of off-heap? Does bigger Memtable would have impact on GC and overall memory management? I am using DSE 3.0 / Cassandra 1.1.9. Thanks, Jay Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.
RE: Reduce Cassandra GC
How one could provide any help without any knowledge about your cluster, node and environment settings? 40GB was calculated from 2 nodes with RF=2 (each has 100% data range), 2.4-2.5M rows * 6 cols * 3kB as a minimum without compression and any overhead (sstable, bloom filters and indexes). With ParNew GC time such as yours even if it is a swapping issue I could say only that heap size is too small. Check Heap, New Heap sizes, memtable and cache sizes. Are you on Linux? Is JNA installed and used? What is total amount of RAM? Just for a DEV environment we use 3 virtual machines with 4GB RAM and use 2GB heap without any GC issue with amount of data from 0 to 16GB compressed on each node. Memtable space sized to 100MB, New Heap 400MB. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider Take a ride with Adform's Rich Media Suitehttp://vimeo.com/adform/richmedia [Adform News] http://www.adform.com [Adform awarded the Best Employer 2012] http://www.adform.com/site/blog/adform/adform-takes-top-spot-in-best-employer-survey/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Joel Samuelsson [mailto:samuelsson.j...@gmail.com] Sent: Tuesday, April 16, 2013 12:52 To: user@cassandra.apache.org Subject: Re: Reduce Cassandra GC How do you calculate the heap / data size ratio? Is this a linear ratio? Each node has slightly more than 12 GB right now though. 2013/4/16 Viktor Jevdokimov viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com For a 40GB of data 1GB of heap is too low. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063tel:%2B370%205%20212%203063, Fax +370 5 261 0453tel:%2B370%205%20261%200453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider Take a ride with Adform's Rich Media Suitehttp://vimeo.com/adform/richmedia [Adform News]http://www.adform.com [Adform awarded the Best Employer 2012]http://www.adform.com/site/blog/adform/adform-takes-top-spot-in-best-employer-survey/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Joel Samuelsson [mailto:samuelsson.j...@gmail.commailto:samuelsson.j...@gmail.com] Sent: Tuesday, April 16, 2013 10:47 To: user@cassandra.apache.orgmailto:user@cassandra.apache.org Subject: Reduce Cassandra GC Hi, We have a small production cluster with two nodes. The load on the nodes is very small, around 20 reads / sec and about the same for writes. There are around 2.5 million keys in the cluster and a RF of 2. About 2.4 million of the rows are skinny (6 columns) and around 3kb in size (each). Currently, scripts are running, accessing all of the keys in timeorder to do some calculations. While running the scripts, the nodes go down and then come back up 6-7 minutes later. This seems to be due to GC. I get lines like this in the log: INFO [ScheduledTasks:1] 2013-04-15 14:00:02,749 GCInspector.java (line 122) GC for ParNew: 338798 ms for 1 collections, 592212416 used; max is 1046937600 However, the heap is not full. The heap usage has a jagged pattern going from 60% up to 70% during 5 minutes and then back down to 60% the next 5 minutes and so on. I get no Heap is X full... messages. Every once in a while at one of these peaks, I get these stop-the-world GC for 6-7 minutes. Why does GC take up so much time even though the heap isn't full? I am aware that my access patterns make key caching very unlikely to be high. And indeed, my average key cache hit ratio during the run of the scripts is around 0.5%. I tried disabling key caching on the accessed column family (UPDATE COLUMN FAMILY cf WITH caching=none;) through the cassandra-cli but I get the same behaviour. Is the turning key cache off effective immediately? Stop-the-world GC is fine
RE: 'sstableloader' is not recognized as an internal or external command,
If your Cassandra cluster is on Linux, I believe that streaming is not supported in mixed environment, i.e. Cassandra nodes can't stream between Windows and Linux and sstableloader can't stream feom Windows to Linux. If your Cassandra also on Windows, just try to create bat file for sstableloader using other bat files for example. I don't know if sstableloader will support Windows directory structure. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider Take a ride with Adform's Rich Media Suitehttp://vimeo.com/adform/richmedia [Adform News] http://www.adform.com [Adform awarded the Best Employer 2012] http://www.adform.com/site/blog/adform/adform-takes-top-spot-in-best-employer-survey/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Techy Teck [mailto:comptechge...@gmail.com] Sent: Tuesday, April 23, 2013 09:10 To: user Subject: 'sstableloader' is not recognized as an internal or external command, I have bunch of `SSTables` with me that I got from somebody within my team. Now I was trying to push those `SSTABLES` into `Cassandra database`. I created corresponding keyspace and column family successfully. Now as soon as I execute `SSTableLoader` command, I always get below exception? S:\Apache Cassandra\apache-cassandra-1.2.3\binsstableloader C:\CassandraClient-LnP\20130405\profileks\PROFILECF 'sstableloader' is not recognized as an internal or external command, operable program or batch file. Can anyone tell me what wrong I am doing here? I am running Cassandra 1.2.3. And this is my first time working with `SSTableLoader`. I am working in windows environment. Is sstableloader supported in windows, looking at the source it seems to be unix shell file? inline: signature-logo29.pnginline: signature-best-employer-logo4823.png
Re: Cassandra Statistics and Metrics
We're using open source monitoring solution Zabbix from http://www.zabbix.com/ using zapcat - not only for Cassandra but for the whole system. As MX4J tools plugin is supported by Cassandra, support of zapcat in Cassandra by default is welcome - we have to use a wrapper to start zapcat agent. 2011/6/14 Marcos Ortiz mlor...@uci.cu Regards to all. My team and me here on the University are working on a generic solution for Monitoring and Capacity Planning for Open Sources Databases, and one of the NoSQL db that we choosed to give it support is Cassandra. Where I can find all the metrics and statistics of Cassandra? I'm thinking for example: - Available space - Number of CF and all kind of metrics We are using for this development: Python + Django + Twisted + Orbited + jQuery. The idea behind is to build a Comet-based web application on top of these technologies. Any advice is welcome -- Marcos Luís Ortíz Valmaseda Software Engineer (UCI) http://marcosluis2186.posterous.com http://twitter.com/marcosluis2186
Re: Cassandra Statistics and Metrics
http://www.kjkoster.org/zapcat/Zapcat_JMX_Zabbix_Bridge.html 2011/6/14 Marcos Ortiz mlor...@uci.cu Where I can find the source code? El 6/14/2011 10:13 AM, Viktor Jevdokimov escribió: We're using open source monitoring solution Zabbix from http://www.zabbix.com/ using zapcat - not only for Cassandra but for the whole system. As MX4J tools plugin is supported by Cassandra, support of zapcat in Cassandra by default is welcome - we have to use a wrapper to start zapcat agent. 2011/6/14 Marcos Ortiz mlor...@uci.cu Regards to all. My team and me here on the University are working on a generic solution for Monitoring and Capacity Planning for Open Sources Databases, and one of the NoSQL db that we choosed to give it support is Cassandra. Where I can find all the metrics and statistics of Cassandra? I'm thinking for example: - Available space - Number of CF and all kind of metrics We are using for this development: Python + Django + Twisted + Orbited + jQuery. The idea behind is to build a Comet-based web application on top of these technologies. Any advice is welcome -- Marcos Luís Ortíz Valmaseda Software Engineer (UCI) http://marcosluis2186.posterous.com http://twitter.com/marcosluis2186 -- Marcos Luís Ortíz Valmaseda Software Engineer (UCI) http://marcosluis2186.posterous.com http://twitter.com/marcosluis2186
Re: possible 'coming back to life' bug with counters
What if it is OK for our case and we need counters with TTL? For us Counters and TTL both are important. After column is expired it is not important what value counter will have. Scanning millions rows just to delete expired ones is not a solution. 2011/6/14 Sylvain Lebresne sylv...@datastax.com As listed here: http://wiki.apache.org/cassandra/Counters, counter deletion is provided as a convenience for permanent deletion of counters but, because of the design of counters, it is never safe to issue an increment on a counter that has been deleted (that is, you will experience back to life behavior sometimes in that case). More precisely, you'd have to wait long enough after a deletion to start incrementing the counter again. But in the worst cases, long enough is something like gc_grace_seconds + major compaction. This is *not* something that is likely to change anytime soon (I don't think this is fixable with the current design for counters). -- Sylvain On Sat, Jun 11, 2011 at 3:54 AM, David Hawthorne dha...@3crowd.com wrote: Please take a look at this thread over in the hector-users mailing list: http://groups.google.com/group/hector-users/browse_thread/thread/99835159b9ea1766 It looks as if the deleted columns are coming back to life when they shouldn't be. I don't want to open a bug on something if it's already got one that I just couldn't find when I scanned the list of open bugs. I'm using hector 0.8 against cassandra 0.8 release. I can give you whatever logs or files you'd like.
Re: Cassandra Statistics and Metrics
There's possibility to use command line JMX client with standard Zabbix agent to request JMX counters without incorporating zapcat into Cassandra or another Java app. I'm investigating this feature right now, will post results when finish. 2011/6/15 Viktor Jevdokimov vjevdoki...@gmail.com http://www.kjkoster.org/zapcat/Zapcat_JMX_Zabbix_Bridge.html 2011/6/14 Marcos Ortiz mlor...@uci.cu Where I can find the source code? El 6/14/2011 10:13 AM, Viktor Jevdokimov escribió: We're using open source monitoring solution Zabbix from http://www.zabbix.com/ using zapcat - not only for Cassandra but for the whole system. As MX4J tools plugin is supported by Cassandra, support of zapcat in Cassandra by default is welcome - we have to use a wrapper to start zapcat agent. 2011/6/14 Marcos Ortiz mlor...@uci.cu Regards to all. My team and me here on the University are working on a generic solution for Monitoring and Capacity Planning for Open Sources Databases, and one of the NoSQL db that we choosed to give it support is Cassandra. Where I can find all the metrics and statistics of Cassandra? I'm thinking for example: - Available space - Number of CF and all kind of metrics We are using for this development: Python + Django + Twisted + Orbited + jQuery. The idea behind is to build a Comet-based web application on top of these technologies. Any advice is welcome -- Marcos Luís Ortíz Valmaseda Software Engineer (UCI) http://marcosluis2186.posterous.com http://twitter.com/marcosluis2186 -- Marcos Luís Ortíz Valmaseda Software Engineer (UCI) http://marcosluis2186.posterous.com http://twitter.com/marcosluis2186
How to enable JNA for Cassandra on Windows?
Hi,
I'm trying without success to enable JNA for Cassandra on Windows.
Tried to place JNA 3.3.0 libs jna.jar and platform.jar into Cassandra 0.8.6
lib dir, but getting in log:
Unable to link C library. Native methods will be disabled.
What is missed or what is wrong?
One thing I've found on inet about JNA and Windows is this sample:
// Library is c for unix and msvcrt for windows
String libName = c;
if (System.getProperty(os.name).contains(Windows))
{
libName = msvcrt;
}
// Loading dynamically the library
CInterface demo = (CInterface) Native.loadLibrary(libName, CInterface.class);
from http://www.scriptol.com/programming/jna.php
while in Cassandra:
try
{
Native.register(c);
}
catch (NoClassDefFoundError e)
{
logger.info(JNA not found. Native methods will be disabled.);
}
catch (UnsatisfiedLinkError e)
{
logger.info(Unable to link C library. Native methods will be
disabled.);
}
catch (NoSuchMethodError e)
{
logger.warn(Obsolete version of JNA present; unable to
register C library. Upgrade to JNA 3.2.7 or later);
}
Is it true that for Windows Cassandra should do something like:
if (System.getProperty(os.name).contains(Windows))
{
Native.register(msvcrt);
}
else
{
Native.register(c);
}
Thanks
Viktor
Build Cassandra under Windows
Hello,
I'm trying to build Cassandra 0.8 and 1.0.0 branches with no success on
Windows, getting errors:
...
maven-ant-tasks-retrieve-build:
[artifact:dependencies] Downloading: asm/asm/3.2/asm-3.2-sources.jar from
repository central at http://repo1.maven.org/maven2
[artifact:dependencies] Unable to locate resource in repository
[artifact:dependencies] [INFO] Unable to find resource
'asm:asm:java-source:sources:3.2' in repository central (
http://repo1.maven.org/maven2)
[artifact:dependencies] Downloading: asm/asm/3.2/asm-3.2-sources.jar from
repository apache at
https://repository.apache.org/content/repositories/releases
[artifact:dependencies] Unable to locate resource in repository
...
and so on.
I have checked build/build-dependencies.xml and all files referenced are
downloaded to local maven repository (${user.home}/.m2/repository)
successfully.
Environment:
Windows 7 Professional x64
Ant 1.8.2
JDK 1.6.0 b27
I'm a .NET developer with no experience building JAVA projects with ant.
What have I missed?
Thanks,
Viktor
RE: Build Cassandra under Windows
Spolved - just used appropriate ant's targets to get jars built.
Best regards/ Pagarbiai
Viktor Jevdokimov
Senior Developer
Email: viktor.jevdoki...@adform.com
Phone: +370 5 212 3063. Fax: +370 5 261 0453
J. Jasinskio 16C, LT-01112 Vilnius, Lithuania
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message in error, please contact the sender immediately and irrevocably delete
this message and any copies.
From: Viktor Jevdokimov [mailto:vjevdoki...@gmail.com]
Sent: Friday, September 23, 2011 10:02
To: user@cassandra.apache.org
Subject: Build Cassandra under Windows
Hello,
I'm trying to build Cassandra 0.8 and 1.0.0 branches with no success on
Windows, getting errors:
...
maven-ant-tasks-retrieve-build:
[artifact:dependencies] Downloading: asm/asm/3.2/asm-3.2-sources.jar from
repository central at http://repo1.maven.org/maven2
[artifact:dependencies] Unable to locate resource in repository
[artifact:dependencies] [INFO] Unable to find resource
'asm:asm:java-source:sources:3.2' in repository central
(http://repo1.maven.org/maven2)
[artifact:dependencies] Downloading: asm/asm/3.2/asm-3.2-sources.jar from
repository apache at https://repository.apache.org/content/repositories/releases
[artifact:dependencies] Unable to locate resource in repository
...
and so on.
I have checked build/build-dependencies.xml and all files referenced are
downloaded to local maven repository (${user.home}/.m2/repository) successfully.
Environment:
Windows 7 Professional x64
Ant 1.8.2
JDK 1.6.0 b27
I'm a .NET developer with no experience building JAVA projects with ant.
What have I missed?
Thanks,
Viktor
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RE: How to enable JNA for Cassandra on Windows?
I found that there's no C library under Windows, and msvcrt does not provide
mlockall function, so currently there's no way to use JNA under Windows. That
way mmap is not a good idea?
Best regards/ Pagarbiai
Viktor Jevdokimov
Senior Developer
Email: viktor.jevdoki...@adform.com
Phone: +370 5 212 3063. Fax: +370 5 261 0453
J. Jasinskio 16C, LT-01112 Vilnius, Lithuania
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this message and any copies.
From: Viktor Jevdokimov [mailto:vjevdoki...@gmail.com]
Sent: Thursday, September 22, 2011 15:01
To: user@cassandra.apache.org
Subject: How to enable JNA for Cassandra on Windows?
Hi,
I'm trying without success to enable JNA for Cassandra on Windows.
Tried to place JNA 3.3.0 libs jna.jar and platform.jar into Cassandra 0.8.6 lib
dir, but getting in log:
Unable to link C library. Native methods will be disabled.
What is missed or what is wrong?
One thing I've found on inet about JNA and Windows is this sample:
// Library is c for unix and msvcrt for windows
String libName = c;
if (System.getProperty(os.namehttp://os.name).contains(Windows))
{
libName = msvcrt;
}
// Loading dynamically the library
CInterface demo = (CInterface) Native.loadLibrary(libName, CInterface.class);
from http://www.scriptol.com/programming/jna.php
while in Cassandra:
try
{
Native.register(c);
}
catch (NoClassDefFoundError e)
{
logger.infohttp://logger.info(JNA not found. Native methods will be
disabled.);
}
catch (UnsatisfiedLinkError e)
{
logger.infohttp://logger.info(Unable to link C library. Native
methods will be disabled.);
}
catch (NoSuchMethodError e)
{
logger.warn(Obsolete version of JNA present; unable to register C
library. Upgrade to JNA 3.2.7 or later);
}
Is it true that for Windows Cassandra should do something like:
if (System.getProperty(os.namehttp://os.name).contains(Windows))
{
Native.register(msvcrt);
}
else
{
Native.register(c);
}
Thanks
Viktor
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RE: shutdown by drain
More of it, Cassandra 0.8.6 still leaves all commit logs under Windows. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.-Original Message- From: Radim Kolar [mailto:h...@sendmail.cz] Sent: Friday, September 23, 2011 12:04 To: user@cassandra.apache.org Subject: Re: shutdown by drain Dne 10.9.2011 21:48, Chris Goffinet napsal(a): For things like rolling restarts, we do: disablethrift disablegossip (...wait for all nodes to see this node go down..) drain I discovered problem with this advice. If i do nodetool drain before killing node nodetool returns just after flush and stuff disabling is finished on cassandra node. But flush can trigger possible compaction and if you kill node after drain it will interrupt compaction in progress resulting in wasted disk space. I am not sure if tmp files are cleaned on cassandra start.
RE: [RELEASE] Apache Cassandra 1.0 released
Congrats!!! Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.-Original Message- From: Sylvain Lebresne [mailto:sylv...@datastax.com] Sent: Tuesday, October 18, 2011 15:02 To: user@cassandra.apache.org Subject: [RELEASE] Apache Cassandra 1.0 released The Cassandra team is very pleased to announce the release of Apache Cassandra version 1.0.0. Cassandra 1.0.0 is a new major release that build upon the awesomeness of previous versions and adds numerous improvements[1,2], amongst which: - Compression of on-disk data files (SSTables), with checksummed blocks to protect against bitrot[4]. - Improvements to memory management through off-heap caches, arena allocation and automatic self-tuning, for less GC pauses and more predictable performances[5]. - Better disk-space management: better control of the space taken by commit logs and immediate deletion of obsolete data files. - New optional leveled compaction strategy with more predictable performance and fixed sstable size[6]. - Improved hinted handoffs, leading to less need for read repair for better read performances. - Lots of improvements to performance[7], CQL, repair, easier operation, etc[8]... And as is the rule for some time now, rolling upgrades from previous versions are supported, so there is nothing stopping you to get all those goodies right now! Both source and binary distributions of Cassandra 1.0.0 can be downloaded at: http://cassandra.apache.org/download/ Or you can use the debian package available from the project APT repository[3] (you will need to use the 10x series). The download page also link to the CQL drivers that, from this release on, are maintained out of tree[9]. That's all folks! [1]: http://goo.gl/t3qpw (CHANGES.txt) [2]: http://goo.gl/6t0qN (NEWS.txt) [3]: http://wiki.apache.org/cassandra/DebianPackaging [4]: http://www.datastax.com/dev/blog/whats-new-in-cassandra-1-0-compression [5]: http://www.datastax.com/dev/blog/whats-new-in-cassandra-1-0-improved-memory-and-disk-space-management [6]: http://www.datastax.com/dev/blog/leveled-compaction-in-apache-cassandra [7]: http://www.datastax.com/dev/blog/whats-new-in-cassandra-1-0-performance [8]: http://www.datastax.com/dev/blog/whats-new-in-cassandra-1-0-windows-service-new-cql-clients-and-more [9]: http://acunu.com/blogs/eric-evans/cassandra-drivers-released/
RE: Cassandra 1.x and proper JNA setup
Up, also interested in answers to questions below. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.-Original Message- From: Maciej Miklas [mailto:mac.mik...@googlemail.com] Sent: Tuesday, November 01, 2011 11:15 To: user@cassandra.apache.org Subject: Cassandra 1.x and proper JNA setup Hi all, is there any documentation about proper JNA configuration? I do not understand few things: 1) Does JNA use JVM heap settings? 2) Do I need to decrease max heap size while using JNA? 3) How do I limit RAM allocated by JNA? 4) Where can I see / monitor row cache size? 5) I've configured JNA just for test on my dev computer and so far I've noticed serious performance issues (high cpu usage on heavy write load), so I must be doing something wrong I've just copied JNA jars into Cassandra/lib, without installing any native libs. This should not work at all, right? Thanks, Maciej
Can't run cleanup
Cassandra version 0.8.7, after adding new nodes we can't run cleanup on any node. Log reports: Cleanup cannot run before a node has joined the ring New nodes has joined (one by one), all nodes up running, reading, writing... Not sending/receiving any streams on any node for more than 12 hours. Nodetool's info/ring/tpstats/netstats for all nodes looks fine. Restart don't help. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news]http://www.adform.com/ [Visit us!] Follow: [twitter]http://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. inline: signature-logo29.pnginline: dm-exco4823.pnginline: tweet18be.png
RE: Can't run cleanup
Nodetool repair also don't start on all nodes, log is reporting: INFO 15:57:51,070 Starting repair command #2, repairing 0 ranges. INFO 15:57:51,070 Repair command #2 completed successfully Regular read repairs are working as reads and writes. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news]http://www.adform.com/ [Visit us!] Follow: [twitter]http://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Viktor Jevdokimov [mailto:viktor.jevdoki...@adform.com] Sent: Wednesday, November 30, 2011 15:14 To: user@cassandra.apache.org Subject: Can't run cleanup Cassandra version 0.8.7, after adding new nodes we can't run cleanup on any node. Log reports: Cleanup cannot run before a node has joined the ring New nodes has joined (one by one), all nodes up running, reading, writing... Not sending/receiving any streams on any node for more than 12 hours. Nodetool's info/ring/tpstats/netstats for all nodes looks fine. Restart don't help. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news]http://www.adform.com/ [Visit us!] Follow: [twitter]http://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. inline: image001.pnginline: image002.pnginline: image003.pnginline: signature-logo5507.pnginline: dm-exco2d8.pnginline: tweet465.png
NetworkTopologyStrategy bug?
Assume for now we have 1 DC and 1 rack with 3 nodes. Ring will look like: (we use own snitch, which returns DC=0, Rack=0 for this case). AddressDC Rack Token 113427455640312821154458202477256070484 10.0.0.1 0 0 0 10.0.0.2 0 0 56713727820156410577229101238628035242 10.0.0.3 0 0 113427455640312821154458202477256070484 Schema: ReplicaPlacementStrategy=NetworkTopologyStrategy, options: [0:2] (2 replicas in DC 0). When trying to run cleanup (same problem with repair), Cassandra reports: From 10.0.0.1: DEBUG [time] 10.0.0.2,10.0.0.3 endpoints in datacenter 0 for token 0 DEBUG [time] 10.0.0.2,10.0.0.3 endpoints in datacenter 0 for token 56713727820156410577229101238628035242 DEBUG [time] 10.0.0.3,10.0.0.2 endpoints in datacenter 0 for token 113427455640312821154458202477256070484 INFO [time] Cleanup cannot run before a node has joined the ring From 10.0.0.2: DEBUG [time] 10.0.0.1,10.0.0.3 endpoints in datacenter 0 for token 0 DEBUG [time] 10.0.0.1,10.0.0.3 endpoints in datacenter 0 for token 56713727820156410577229101238628035242 DEBUG [time] 10.0.0.3,10.0.0.1 endpoints in datacenter 0 for token 113427455640312821154458202477256070484 INFO [time] Cleanup cannot run before a node has joined the ring From 10.0.0.3: DEBUG [time] 10.0.0.1,10.0.0.2 endpoints in datacenter 0 for token 0 DEBUG [time] 10.0.0.1,10.0.0.2 endpoints in datacenter 0 for token 56713727820156410577229101238628035242 DEBUG [time] 10.0.0.2,10.0.0.1 endpoints in datacenter 0 for token 113427455640312821154458202477256070484 INFO [time] Cleanup cannot run before a node has joined the ring For me this means, that one node thinks that whole data range is on other two nodes. As a result: WRITE request with any key/any token sent to 10.0.0.1 controller will be forwarded and saved on 10.0.0.2 and 10.0.0.3 READ request with CL.One with any key/any token sent to 10.0.0.2 controller will be forwarded to 10.0.0.1 or 10.0.0.3, and since 10.0.0.1 can't have data for write above, some requests fails, some don't (if 10.0.0.3 answers). More of it, every READ request to any node will be forwarded to other node. That what we have right now with 0.8.6 and up to 1.0.5 as with 3 nodes in 1 DC, as with 8x2 nodes. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news]http://www.adform.com/ [Visit us!] Follow: [twitter]http://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. inline: signature-logo29.pnginline: dm-exco4823.pnginline: tweet18be.png
RE: NetworkTopologyStrategy bug?
Sorry, the bug was in our snitch. We're using getHostName() instead of getCanonicalHostName() to determine DC Rack and since for local it returns alias, instead of reverse DNS, DC Rack numbers are not as expected. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news]http://www.adform.com/ [Visit us!] Follow: [twitter]http://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Viktor Jevdokimov [mailto:viktor.jevdoki...@adform.com] Sent: Thursday, December 01, 2011 14:05 To: user@cassandra.apache.org Subject: NetworkTopologyStrategy bug? Assume for now we have 1 DC and 1 rack with 3 nodes. Ring will look like: (we use own snitch, which returns DC=0, Rack=0 for this case). AddressDC Rack Token 113427455640312821154458202477256070484 10.0.0.1 0 0 0 10.0.0.2 0 0 56713727820156410577229101238628035242 10.0.0.3 0 0 113427455640312821154458202477256070484 Schema: ReplicaPlacementStrategy=NetworkTopologyStrategy, options: [0:2] (2 replicas in DC 0). When trying to run cleanup (same problem with repair), Cassandra reports: From 10.0.0.1: DEBUG [time] 10.0.0.2,10.0.0.3 endpoints in datacenter 0 for token 0 DEBUG [time] 10.0.0.2,10.0.0.3 endpoints in datacenter 0 for token 56713727820156410577229101238628035242 DEBUG [time] 10.0.0.3,10.0.0.2 endpoints in datacenter 0 for token 113427455640312821154458202477256070484 INFO [time] Cleanup cannot run before a node has joined the ring From 10.0.0.2: DEBUG [time] 10.0.0.1,10.0.0.3 endpoints in datacenter 0 for token 0 DEBUG [time] 10.0.0.1,10.0.0.3 endpoints in datacenter 0 for token 56713727820156410577229101238628035242 DEBUG [time] 10.0.0.3,10.0.0.1 endpoints in datacenter 0 for token 113427455640312821154458202477256070484 INFO [time] Cleanup cannot run before a node has joined the ring From 10.0.0.3: DEBUG [time] 10.0.0.1,10.0.0.2 endpoints in datacenter 0 for token 0 DEBUG [time] 10.0.0.1,10.0.0.2 endpoints in datacenter 0 for token 56713727820156410577229101238628035242 DEBUG [time] 10.0.0.2,10.0.0.1 endpoints in datacenter 0 for token 113427455640312821154458202477256070484 INFO [time] Cleanup cannot run before a node has joined the ring For me this means, that one node thinks that whole data range is on other two nodes. As a result: WRITE request with any key/any token sent to 10.0.0.1 controller will be forwarded and saved on 10.0.0.2 and 10.0.0.3 READ request with CL.One with any key/any token sent to 10.0.0.2 controller will be forwarded to 10.0.0.1 or 10.0.0.3, and since 10.0.0.1 can't have data for write above, some requests fails, some don't (if 10.0.0.3 answers). More of it, every READ request to any node will be forwarded to other node. That what we have right now with 0.8.6 and up to 1.0.5 as with 3 nodes in 1 DC, as with 8x2 nodes. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news]http://www.adform.com/ [Visit us!] Follow: [twitter]http://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. inline: image001.pnginline: image002.pnginline: image003.pnginline: signature-logo46e2.pnginline: dm-exco578c.pnginline: tweet7db.png
RE: cassandra most stable version ?
0.8.7 Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news]http://www.adform.com/ [Visit us!] Follow: [twitter]http://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Pierre Chalamet [mailto:pie...@chalamet.net] Sent: Wednesday, December 07, 2011 00:05 To: user@cassandra.apache.org Subject: cassandra most stable version ? Hello, Recent problems with Cassandra 1.0.x versions seems to tell it is still not ready for prime time. We are currently using version 0.8.5 on our development cluster - although we have not seen much problems with this one, maybe recent versions of 0.8.x might be safer to use. So what version are you running in production ? What kinds of problems do you encounter if any ? Thanks, - Pierre inline: signature-logo29.pnginline: dm-exco4823.pnginline: tweet18be.png
RE: [RELEASE] Apache Cassandra 1.0.6 released
Cassandra 1.0.6 under Windows Server 2008 R2 64bit with disk acces mode mmap_index_only failing to delete any *-Index.db files after compaction or scrub: ERROR 13:43:17,490 Fatal exception in thread Thread[NonPeriodicTasks:1,5,main] java.lang.RuntimeException: java.io.IOException: Failed to delete D:\cassandra\data\data\system\LocationInfo-g-29-Index.db at org.apache.cassandra.utils.FBUtilities.unchecked(FBUtilities.java:689) at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:34) at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source) at java.util.concurrent.FutureTask.run(Unknown Source) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(Unknown Source) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source) Caused by: java.io.IOException: Failed to delete D:\cassandra\data\data\system\LocationInfo-g-29-Index.db at org.apache.cassandra.io.util.FileUtils.deleteWithConfirm(FileUtils.java:54) at org.apache.cassandra.io.util.FileUtils.deleteWithConfirm(FileUtils.java:44) at org.apache.cassandra.io.sstable.SSTable.delete(SSTable.java:141) at org.apache.cassandra.io.sstable.SSTableDeletingTask.runMayThrow(SSTableDeletingTask.java:81) at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:30) ... 8 more ERROR 17:20:09,701 Fatal exception in thread Thread[NonPeriodicTasks:1,5,main] java.lang.RuntimeException: java.io.IOException: Failed to delete D:\cassandra\data\data\Keyspace1\ColumnFamily1-hc-840-Index.db at org.apache.cassandra.utils.FBUtilities.unchecked(FBUtilities.java:689) at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:34) at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source) at java.util.concurrent.FutureTask.run(Unknown Source) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(Unknown Source) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source) Caused by: java.io.IOException: Failed to delete D:\cassandra\data\data\ Keyspace1\ColumnFamily1-hc-840-Index.db at org.apache.cassandra.io.util.FileUtils.deleteWithConfirm(FileUtils.java:54) at org.apache.cassandra.io.util.FileUtils.deleteWithConfirm(FileUtils.java:44) at org.apache.cassandra.io.sstable.SSTable.delete(SSTable.java:141) at org.apache.cassandra.io.sstable.SSTableDeletingTask.runMayThrow(SSTableDeletingTask.java:81) at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:30) ... 8 more Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.-Original Message- From: Sylvain Lebresne [mailto:sylv...@datastax.com] Sent: Wednesday, December 14, 2011 20:23 To: user@cassandra.apache.org Subject: [RELEASE] Apache Cassandra 1.0.6 released The Cassandra team is pleased to announce the release of Apache Cassandra version 1.0.6. Cassandra is a highly scalable second-generation distributed database, bringing together Dynamo's fully distributed design and Bigtable's ColumnFamily-based data model. You can read more here: http://cassandra.apache.org/ Downloads of source and binary distributions are listed in our download section: http://cassandra.apache.org/download/ This version is maintenance/bug fix release[1]. As always, please pay attention to the release notes[2] and Let us know[3] if you were to encounter any problem. Have fun! [1]: http://goo.gl/Pl1TE (CHANGES.txt) [2]: http://goo.gl/9xHEC (NEWS.txt) [3]: https://issues.apache.org/jira/browse/CASSANDRA
RE: [RELEASE] Apache Cassandra 1.0.6 released
Created https://issues.apache.org/jira/browse/CASSANDRA-3642 -Original Message- From: Viktor Jevdokimov [mailto:viktor.jevdoki...@adform.com] Sent: Thursday, December 15, 2011 18:26 To: user@cassandra.apache.org Subject: RE: [RELEASE] Apache Cassandra 1.0.6 released Cassandra 1.0.6 under Windows Server 2008 R2 64bit with disk acces mode mmap_index_only failing to delete any *-Index.db files after compaction or scrub: ERROR 13:43:17,490 Fatal exception in thread Thread[NonPeriodicTasks:1,5,main] java.lang.RuntimeException: java.io.IOException: Failed to delete D:\cassandra\data\data\system\LocationInfo-g-29-Index.db at org.apache.cassandra.utils.FBUtilities.unchecked(FBUtilities.java:689) at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:34) at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source) at java.util.concurrent.FutureTask.run(Unknown Source) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(Unknown Source) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source) Caused by: java.io.IOException: Failed to delete D:\cassandra\data\data\system\LocationInfo-g-29-Index.db at org.apache.cassandra.io.util.FileUtils.deleteWithConfirm(FileUtils.java:54) at org.apache.cassandra.io.util.FileUtils.deleteWithConfirm(FileUtils.java:44) at org.apache.cassandra.io.sstable.SSTable.delete(SSTable.java:141) at org.apache.cassandra.io.sstable.SSTableDeletingTask.runMayThrow(SSTableDeletingTask.java:81) at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:30) ... 8 more ERROR 17:20:09,701 Fatal exception in thread Thread[NonPeriodicTasks:1,5,main] java.lang.RuntimeException: java.io.IOException: Failed to delete D:\cassandra\data\data\Keyspace1\ColumnFamily1-hc-840-Index.db at org.apache.cassandra.utils.FBUtilities.unchecked(FBUtilities.java:689) at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:34) at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source) at java.util.concurrent.FutureTask.run(Unknown Source) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(Unknown Source) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source) Caused by: java.io.IOException: Failed to delete D:\cassandra\data\data\ Keyspace1\ColumnFamily1-hc-840-Index.db at org.apache.cassandra.io.util.FileUtils.deleteWithConfirm(FileUtils.java:54) at org.apache.cassandra.io.util.FileUtils.deleteWithConfirm(FileUtils.java:44) at org.apache.cassandra.io.sstable.SSTable.delete(SSTable.java:141) at org.apache.cassandra.io.sstable.SSTableDeletingTask.runMayThrow(SSTableDeletingTask.java:81) at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:30) ... 8 more Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.-Original Message- From: Sylvain Lebresne [mailto:sylv...@datastax.com] Sent: Wednesday, December 14, 2011 20:23 To: user@cassandra.apache.org Subject: [RELEASE] Apache Cassandra 1.0.6 released The Cassandra team is pleased to announce the release of Apache Cassandra version 1.0.6. Cassandra is a highly scalable second-generation distributed database, bringing together Dynamo's fully distributed design and Bigtable's ColumnFamily-based data model. You can read more here: http://cassandra.apache.org/ Downloads of source and binary distributions are listed in our download section: http://cassandra.apache.org/download/ This version is maintenance/bug fix release[1]. As always, please pay attention
Leveled compaction strategy and expiring columns
Hi, We're trying to understand how leveled compaction works. The documentation written is about new/updated columns only. What about expiring columns and TTL? When higher level sstables will be compacted and expired columns removed? Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news]http://www.adform.com/ [Visit us!] Follow: [twitter]http://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. inline: signature-logo29.pnginline: dm-exco4823.pnginline: tweet18be.png
Re: How to control location of data?
The idea behind client that controls location of a data is performance, to avoid unnecessary network round-trips between nodes and unnecessary caching of backup ranges. All of this mostly is true for reads at CL.ONE and RF1. How it works (in our case): Our client uses describe_ring that returns ring for specified Keyspace with token ranges and replica endpoints for each range. First node in the list for a token range is a kind of a primary, others are backup replicas. The client for most requests for a single key calculates a token and connects to node that is a primary node for this token. If primary is down, next endpoint from the list of endpoints for that token range is used. This way the network load between nodes is much lower. In our case, when load balancing just rotated all nodes we've seen a 100Mbps load on a node, while with an approach above 25Mbps only. Caches on a single node is filled up with data of a primary range of that node, avoiding of caching replica ranges that also belongs to this node by RF. The downside is when primary node is not accessible, backup node has no cache for a range we're switched to. 2012/1/11 Andreas Rudolph andreas.rudo...@spontech-spine.com Hi! ... Again, it's probably a bad idea. I agree on that, now. Thank you. Cheers - Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 11/01/2012, at 4:56 AM, Roland Gude wrote: ** ** Each node in the cluster is assigned a token (can be done automatically – but usually should not) The token of a node is the start token of the partition it is responsible for (and the token of the next node is the end token of the current tokens partition) ** ** Assume you have the following nodes/tokens (which are usually numbers but for the example I will use letters) ** ** N1/A N2/D N3/M N4/X ** ** This means that N1 is responsible (primary) for [A-D) N2 for [D-M) N3 for [M-X) And N4 for [X-A) ** ** If you have a replication factor of 1 data will go on the nodes like this: ** ** B - N1 E-N2 X-N4 ** ** And so on If you have a higher replication factor, the placement strategy decides which node will take replicas of which partition (becoming secondary node for that partition) Simple strategy will just put the replica on the next node in the ring So same example as above but RF of 2 and simple strategy: ** ** B- N1 and N2 E - N2 and N3 X - N4 and N1 ** ** Other strategies can factor in things like “put data in another datacenter” or “put data in another rack” or such things. ** ** Even though the terms primary and secondary imply some means of quality or consistency, this is not the case. If a node is responsible for a piece of data, it will store it. ** ** ** ** But placement of the replicas is usually only relevant for availability reasons (i.e. disaster recovery etc.) Actual location should mean nothing to most applications as you can ask any node for the data you want and it will provide it to you (fetching it from the responsible nodes). This should be sufficient in almost all cases. ** ** So in the above example again, you can ask N3 “what data is available” and it will tell you: B, E and X, or you could ask it “give me X” and it will fetch it from N4 or N1 or both of them depending on consistency configuration and return the data to you. ** ** ** ** So actually if you use Cassandra – for the application the actual storage location of the data should not matter. It will be available anywhere in the cluster if it is stored on any reachable node. ** ** *Von:* Andreas Rudolph [mailto:andreas.rudo...@spontech-spine.com] *Gesendet:* Dienstag, 10. Januar 2012 15:06 *An:* user@cassandra.apache.org *Betreff:* Re: AW: How to control location of data? ** ** Hi! ** ** Thank you for your last reply. I'm still wondering if I got you right...** ** ** ** ... A partitioner decides into which partition a piece of data belongs Does your statement imply that the partitioner does not take any decisions at all on the (physical) storage location? Or put another way: What do you mean with partition? ** ** To quote http://wiki.apache.org/cassandra/ArchitectureInternals: ... AbstractReplicationStrategy controls what nodes get secondary, tertiary, etc. replicas of each key range. Primary replica is always determined by the token ring (...) ... You can select different placement strategies and partitioners for different keyspaces, thereby choosing known data to be stored on known hosts. This is however discouraged for various reasons – i.e. you need a lot of knowledge about your data to keep the cluster balanced. What is your usecase for this requirement? there is probably a more suitable solution.* *** What we want is to
RE: SQL DB Integration
Hello Krassimir, From a typical programmer you should receive an answer, that this is possible, but easy or difficult - depends. From a typical consultand you should receive a question - why? I am working on a project, for which I have to evaluate and recommend the implementation of a new database system, with the following major characteristics: * Operational scalability Not advisable to do this automatically, do it manually. * Low cost Compared to what? * Ability to serve both as a data storage facility and an advanced data manipulation tool Cassandra is not a data manipulaiton tool. * Speed of execution Execution of what? * Real-time writing capability, with potential to record millions of client data records in real time Millions per second/minute/hour/day? Isn't any DB capable of this? * Flexibility: ability to support all client data types and formats, structured and unstructured Data types supported are limited, others as binary arrays. * Capability to support multiple data centers and geographies Capable. * Ability to provide data infrastructure solutions for clients with small and Big Data needs Same soluiton for all? Will it be cost/performance/maintenance/support effective for all? * Full and flawless integration with the following 3 infrastructures: (1) A data mining application (IBM SPSS Modeler) that imports/exports data from/to an SQL database (2) A partner platform, based on an Oracle Database (CSV data import/export) (3) Various client SQL databases, whose data elements will be uploaded and replicated in the recommended database system Cassandra (almost any storage) does not provide any integration. Integration is built upon storage APIs. As a result to my research, I am planning to recommend the implementation of Apache Cassandra NoSQL DB, hosted on Amazon Elastic Compute Cloud (Amazon EC2). I realize that the biggest challenge from the above 3 points is probably the last one, since for each client we need to custom-build and replicate their database, changing the data model from SQL to NoSQL. The reason being that (1) and (2) relate only to transferring data up and down between SQL and NoSQL environments. My question is how easy/difficult is it to build a GUI/API that will be able to do the integration in the above 3 points with respect to transferring data (upstream / downstream) between the Cassandra NoSQL NoSQL environments? Do you have any other comments or suggestions that I should consider? In my opinion you should do your research for Cassandra on specific questions, not global. First, define storage requirements from application/functionality perspective, then look for a solution. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.
Consurrent compactors
Hi, When concurrent compactors are set to more then 1, it's rare when more than 1 compaction is running in parallel. Didn't checked the source code, but it looks like when next compaction task (any of minor, major, or cleanup) is for the same CF, it will not start in parallel and next tasks are not checked. Will it be possible to check all tasks, not only the next one, to find which of them can be started? This is actual especially when nightly cleanup is running, a lot of cleanup tasks are pending, regular minor compactions are waiting until all cleanup compactions are finished. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news]http://www.adform.com/ [Visit us!] Follow: [twitter]http://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. inline: signature-logo29.pnginline: dm-exco4823.pnginline: tweet18be.png
RE: Consurrent compactors
My concern is not anout cleanup, but about supposed tendency of small sstables to accumulate during a single long running compactions. When next task is for the same column family as currently long-running compaction, other column families compactions are freezed and concurrent_compactors 1 setting just not working. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news]http://www.adform.com/ [Visit us!] Follow: [twitter]http://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: aaron morton [mailto:aa...@thelastpickle.com] Sent: Wednesday, February 01, 2012 21:51 To: user@cassandra.apache.org Subject: Re: Consurrent compactors (Assuming 1.0* release) From the comments in cassandra.yaml # Number of simultaneous compactions to allow, NOT including # validation compactions for anti-entropy repair. Simultaneous # compactions can help preserve read performance in a mixed read/write # workload, by mitigating the tendency of small sstables to accumulate # during a single long running compactions. The default is usually # fine and if you experience problems with compaction running too # slowly or too fast, you should look at # compaction_throughput_mb_per_sec first. # # This setting has no effect on LeveledCompactionStrategy. # # concurrent_compactors defaults to the number of cores. # Uncomment to make compaction mono-threaded, the pre-0.8 default. #concurrent_compactors: 1 If you set it to 1 then only 1 compaction should run at a time, excluding validation. How often do you run a cleanup compaction ? They are only necessary when you perform a token move. Cheers - Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 1/02/2012, at 9:48 PM, Viktor Jevdokimov wrote: Hi, When concurrent compactors are set to more then 1, it's rare when more than 1 compaction is running in parallel. Didn't checked the source code, but it looks like when next compaction task (any of minor, major, or cleanup) is for the same CF, it will not start in parallel and next tasks are not checked. Will it be possible to check all tasks, not only the next one, to find which of them can be started? This is actual especially when nightly cleanup is running, a lot of cleanup tasks are pending, regular minor compactions are waiting until all cleanup compactions are finished. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania signature-logo29.pnghttp://www.adform.com/ dm-exco4823.png Follow: tweet18be.pnghttp://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. inline: signature-logo29.pnginline: dm-exco4823.pnginline: tweet18be.png
Internal error processing batch_mutate java.util.ConcurrentModificationException
What may be cause of the following exception in 1.0.7 Cassandra: ERROR [Thrift:134] 2012-02-03 15:51:02,800 Cassandra.java (line 3462) Internal error processing batch_mutate java.util.ConcurrentModificationException at java.util.AbstractList$Itr.checkForComodification(AbstractList.java:372) at java.util.AbstractList$Itr.next(AbstractList.java:343) at org.apache.cassandra.utils.FBUtilities.waitOnFutures(FBUtilities.java:532) at org.apache.cassandra.service.AbstractWriteResponseHandler.waitForHints(AbstractWriteResponseHandler.java:89) at org.apache.cassandra.service.AbstractWriteResponseHandler.get(AbstractWriteResponseHandler.java:58) at org.apache.cassandra.service.StorageProxy.mutate(StorageProxy.java:201) at org.apache.cassandra.thrift.CassandraServer.doInsert(CassandraServer.java:639) at org.apache.cassandra.thrift.CassandraServer.internal_batch_mutate(CassandraServer.java:590) at org.apache.cassandra.thrift.CassandraServer.batch_mutate(CassandraServer.java:598) at org.apache.cassandra.thrift.Cassandra$Processor$batch_mutate.process(Cassandra.java:3454) at org.apache.cassandra.thrift.Cassandra$Processor.process(Cassandra.java:2889) at org.apache.cassandra.thrift.CustomTThreadPoolServer$WorkerProcess.run(CustomTThreadPoolServer.java:187) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:662) Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news]http://www.adform.com/ [Visit us!] Follow: [twitter]http://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. inline: signature-logo4913.pnginline: dm-exco199c.pnginline: tweet3130.png
RE: Internal error processing batch_mutate java.util.ConcurrentModificationException
Yes, the exception is for CounterColumn on Standard column family. Created https://issues.apache.org/jira/browse/CASSANDRA-3870 Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news]http://www.adform.com/ [Visit us!] Follow: [twitter]http://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: aaron morton [mailto:aa...@thelastpickle.com] Sent: Monday, February 06, 2012 21:03 To: user@cassandra.apache.org Subject: Re: Internal error processing batch_mutate java.util.ConcurrentModificationException That looks like a bug. Were you writing counters ? Can you please add it here https://issues.apache.org/jira/browse/CASSANDRA , include some information on the request that caused it and email the bug report back to the list. (note to self) I *think* the problem is the counter WritePerformer implementations are put into the REPLICATE_ON_WRITE TP and then update the hints on the AbstractWriteResponeHandler asynchronously. This could happen after the write thread has move on to wait on the handlers which involves waiting on the hints futures. thanks - Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 4/02/2012, at 4:49 AM, Viktor Jevdokimov wrote: What may be cause of the following exception in 1.0.7 Cassandra: ERROR [Thrift:134] 2012-02-03 15:51:02,800 Cassandra.java (line 3462) Internal error processing batch_mutate java.util.ConcurrentModificationException at java.util.AbstractList$Itr.checkForComodification(AbstractList.java:372) at java.util.AbstractList$Itr.next(AbstractList.java:343) at org.apache.cassandra.utils.FBUtilities.waitOnFutures(FBUtilities.java:532) at org.apache.cassandra.service.AbstractWriteResponseHandler.waitForHints(AbstractWriteResponseHandler.java:89) at org.apache.cassandra.service.AbstractWriteResponseHandler.get(AbstractWriteResponseHandler.java:58) at org.apache.cassandra.service.StorageProxy.mutate(StorageProxy.java:201) at org.apache.cassandra.thrift.CassandraServer.doInsert(CassandraServer.java:639) at org.apache.cassandra.thrift.CassandraServer.internal_batch_mutate(CassandraServer.java:590) at org.apache.cassandra.thrift.CassandraServer.batch_mutate(CassandraServer.java:598) at org.apache.cassandra.thrift.Cassandra$Processor$batch_mutate.process(Cassandra.java:3454) at org.apache.cassandra.thrift.Cassandra$Processor.process(Cassandra.java:2889) at org.apache.cassandra.thrift.CustomTThreadPoolServer$WorkerProcess.run(CustomTThreadPoolServer.java:187) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:662) Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania signature-logo4913.pnghttp://www.adform.com/ dm-exco199c.png Follow: tweet3130.pnghttp://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. inline: signature-logo29.pnginline: dm-exco4823.pnginline: tweet18be.png
Re: how stable is 1.0 these days?
1.0.7 is very stable, weeks in high-load production environment without any exception, 1.0.8 should be even more stable, check changes.txt for what was fixed. 2012/3/2 Marcus Eriksson krum...@gmail.com beware of https://issues.apache.org/jira/browse/CASSANDRA-3820 though if you have many keys per node other than that, yep, it seems solid /Marcus On Wed, Feb 29, 2012 at 6:20 PM, Thibaut Britz thibaut.br...@trendiction.com wrote: Thanks! We will test it on our test cluster in the coming weeks and hopefully put it into production on our 200 node main cluster. :) Thibaut On Wed, Feb 29, 2012 at 5:52 PM, Edward Capriolo edlinuxg...@gmail.comwrote: On Wed, Feb 29, 2012 at 10:35 AM, Thibaut Britz thibaut.br...@trendiction.com wrote: Any more feedback on larger deployments of 1.0.*? We are eager to try out the new features in production, but don't want to run into bugs as on former 0.7 and 0.8 versions. Thanks, Thibaut On Tue, Jan 31, 2012 at 6:59 AM, Ben Coverston ben.covers...@datastax.com wrote: I'm not sure what Carlo is referring to, but generally if you have done, thousands of migrations you can end up in a situation where the migrations take a long time to replay, and there are some race conditions that can be problematic in the case where there are thousands of migrations that may need to be replayed while a node is bootstrapped. If you get into this situation it can be fixed by copying migrations from a known good schema to the node that you are trying to bootstrap. Generally I would advise against frequent schema updates. Unlike rows in column families the schema itself is designed to be relatively static. On Mon, Jan 30, 2012 at 2:14 PM, Jim Newsham jnews...@referentia.com wrote: Could you also elaborate for creating/dropping column families? We're currently working on moving to 1.0 and using dynamically created tables, so I'm very interested in what issues we might encounter. So far the only thing I've encountered (with 1.0.7 + hector 1.0-2) is that dropping a cf may sometimes fail with UnavailableException. I think this happens when the cf is busy being compacted. When I sleep/retry within a loop it eventually succeeds. Thanks, Jim On 1/26/2012 7:32 AM, Pierre-Yves Ritschard wrote: Can you elaborate on the composite types instabilities ? is this specific to hector as the radim's posts suggests ? These one liner answers are quite stressful :) On Thu, Jan 26, 2012 at 1:28 PM, Carlo Pirescarlopi...@gmail.com wrote: If you need to use composite types and create/drop column families on the fly you must be prepared to instabilities. -- Ben Coverston DataStax -- The Apache Cassandra Company I would call 1.0.7 rock fricken solid. Incredibly stable. It has been that way since I updated to 0.8.8 really. TBs of data, billions of requests a day, and thanks to JAMM, memtable type auto-tuning, and other enhancements I rarely, if ever, find a node in a state where it requires a restart. My clusters are beast-ing. There always is bugs in software, but coming from a guy who ran cassandra 0.6.1.Administration on my Cassandra cluster is like a vacation now.
Re: Huge amount of empty files in data directory.
After running Cassandra for 2 years in production on Windows servers, starting from 0.7 beta2 up to 1.0.7 we have moved to Linux and forgot all the hell we had on Windows. Having JNA, off-heap row cache and normally working MMAP on Linux you're getting a lot better performance and stability comparing to Windows, and less maintenance. 2012/3/1 Henrik Schröder skro...@gmail.com Great, thanks! /Henrik On Thu, Mar 1, 2012 at 13:08, Sylvain Lebresne sylv...@datastax.comwrote: It's a bug, namely: https://issues.apache.org/jira/browse/CASSANDRA-3616 You'd want to upgrade. -- Sylvain On Thu, Mar 1, 2012 at 1:01 PM, Henrik Schröder skro...@gmail.com wrote: Hi, We're running Cassandra 1.0.6 on Windows, and noticed that the amount of files in the datadirectory just keeps growing. We have about 60GB of data per node, we do a major compaction about once a week, but after compaction there's a lot of 0-byte temp files and old files that are kept for some reason. After 50 days of uptime there was around 5 files in each datadirectory, but when we restarted a server it deleted all the unnecessary files and it shrunk down to about 200 files. We're running without compression, and with the regular compaction strategy, not leveldb. I don't remember seeing this behaviour in older versions of Cassandra, shouldn't it delete temp files while running? Is it possible to force it to delete temp files while running? Is this fixed in a later version? Or do we have to periodically restart servers to clean up the datadirectories? /Henrik Schröder
Re: Cassandra cache patterns with thiny and wide rows
Depends on how large is a data set, specifically hot data, comparing to available RAM, what is a heavy read load, and what are the latency requirements. 2012/3/6 Maciej Miklas mac.mik...@googlemail.com I've asked this question already on stackoverflow but without answer - I wll try again: My use case expects heavy read load - there are two possible model design strategies: 1. Tiny rows with row cache: In this case row is small enough to fit into RAM and all columns are being cached. Read access should be fast. 2. Wide rows with key cache. Wide rows with large columns amount are to big for row cache. Access to column subset requires HDD seek. As I understand using wide rows is a good design pattern. But we would need to disable row cache - so what is the benefit of such wide row (at least for read access)? Which approach is better 1 or 2?
Truncate flushes memtables for all CFs causing timeouts
Hello, Truncate uses RPC timeout, which is in my case set to 10 seconds (I want even less) and it's not enough. I've seen in sources TODO for this case. What I found is that truncate starting flush for all memtables for all CFs, not only for a CF to be truncated. When there're a lot of CFs to be flushed, it takes time. Is it possible to flush only required CF for truncate, not all? This could improve truncate time. Best regards, Viktor
Re: Truncate flushes memtables for all CFs causing timeouts
Thank you. To sum up, to free up and discard a commit log - flush all. So higher timeout for truncate will/should work. 2012/3/6 aaron morton aa...@thelastpickle.com Truncate uses RPC timeout, which is in my case set to 10 seconds (I want even less) and it's not enough. I've seen in sources TODO for this case. created https://issues.apache.org/jira/browse/CASSANDRA-4006 Is it possible to flush only required CF for truncate, not all? This could improve truncate time. see code comments here https://github.com/apache/cassandra/blob/trunk/src/java/org/apache/cassandra/db/ColumnFamilyStore.java#L1681 AFAIK truncate is not considered a regular operation. (All nodes must be online for example) Cheers - Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 7/03/2012, at 1:34 AM, Viktor Jevdokimov wrote: Hello, Truncate uses RPC timeout, which is in my case set to 10 seconds (I want even less) and it's not enough. I've seen in sources TODO for this case. What I found is that truncate starting flush for all memtables for all CFs, not only for a CF to be truncated. When there're a lot of CFs to be flushed, it takes time. Is it possible to flush only required CF for truncate, not all? This could improve truncate time. Best regards, Viktor
Re: how to increase compaction rate?
After loosing one node we had to repair, CFs was on leveled compaction. For one CF each node had about 7GB of data. Running a repair without primary range switch ended up some nodes exhausted to about 60-100GB of 5MB sstables for that CF (a lot of files). After switching back from leveled to tiered we ended up completely blocked compactions on all nodes since this CF were compacting forever. On one node a major compaction for that CF is CPU bound and may run with unlimited compaction speed for 4-7 days at maximum 1MB/s rate, finally compacting to 3GB of data (some data is deleted by TTL, some merged). What we did to speedup this process to return all exhausted nodes into normal state faster: We have created a 6 temporary virtual single Cassandra nodes with 2 CPU cores and 8GB RAM. Stopped completely a compaction for CF on a production node. Leveled sstables from this production node was divided into 6 ranges and copied into 6 temporary empty nodes. On each node we ran a major compaction to compact just 1/6 of data, about 10-14GB. It took 1-2 hours to compact them into 1GB of data. Then all 6 sstables was copied into one of 6 nodes for a major compaction, finally getting expected 3GB sstable. Stopping production node, deleting files that was copied, returning compacted (may need renaming) and node is back to normal. Using separate nodes we saved original production nodes time not to compact exhausted CF forever, blocking compactions for other CFs. With 6 separate nodes we have compacted 2 productions nodes a day, so maybe it took the same time, but production nodes were free for regular compactions for other CFs. After back to normal for our use case we stick to tiered compaction with a major compaction nightly. With our insertion/TTL deletion rates a leveled compaction is a nightmare, even if amount of data is not very huge, just a few GBs/node. 2012/3/13 Thorsten von Eicken t...@rightscale.com On 3/12/2012 6:52 AM, Brandon Williams wrote: On Mon, Mar 12, 2012 at 4:44 AM, aaron morton aa...@thelastpickle.com wrote: I don't understand why I don't get multiple concurrent compactions running, that's what would make the biggest performance difference. concurrent_compactors Controls how many concurrent compactions to run, by default it's the number of cores on the machine. I'm on a quad-core machine so not setting concurrent_compactors should not be a limiting factor... With leveled compaction, I don't think you get any concurrency because it has to compact an entire level, and it can't proceed to the next level without completing the one before it. In short, if you want maximum throughput, stick with size tiered. I switched the CFs to tiered compaction and I still get no concurrency for the same CF. I now have two compactions running concurrently but always for different CFs. I've briefly seen a third for one of the small CFs, so it's willing to run more than two concurrently. Looks like I have to wait for a few days for all the compactions to complete. Talk about compaction hell! -Brandon
RE: tombstones problem with 1.0.8
Just tested 1.0.8 before upgrading from 1.0.7: tombstones created by TTL or by delete operation are perfectly deleted after either compaction or cleanup. Have no idea about any other settings than gc_grace_seconds, check you schema from cassandra-cli. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news]http://www.adform.com/ [Visit us!] Follow: [twitter]http://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Ross Black [mailto:ross.w.bl...@gmail.com] Sent: Thursday, March 22, 2012 03:38 To: user@cassandra.apache.org Subject: tombstones problem with 1.0.8 Hi, We recently moved from 0.8.2 to 1.0.8 and the behaviour seems to have changed so that tombstones are now not being deleted. Our application continually adds and removes columns from Cassandra. We have set a short gc_grace time (3600) since our application would automatically delete zombies if they appear. Under 0.8.2, the tombstones remained at a relatively constant number. Under 1.0.8, the tombstones have been continually increasing so that they exceed the size of our real data (at this stage we have over 100G of tombstones). Even after running a full compact the new compacted SSTable contains a massive number of tombstones, many that are several weeks old. Have I missed some new configuration option to allow deletion of tombstones? I also noticed that one of the changes between 0.8.2 and 1.0.8 was https://issues.apache.org/jira/browse/CASSANDRA-2786 which changed code to avoid dropping tombstones when they might still be needed to shadow data in another sstable. Could this be having an impact since we continually add and remove columns even while a major compact is executing? Thanks, Ross inline: signature-logo744e.pnginline: dm-exco3c0.pnginline: tweet6005.png
RE: tombstones problem with 1.0.8
Yes, continued deletions of the same columns/rows will prevent removing them from final sstable upon compaction due to new timestamp. You're getting sliding tombstone gc grace period in that case. During compaction of selected sstables Cassandra checks the whole Column Family for the latest timestamp of the column/row, including other sstables and memtable. You need to review your application logic. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news]http://www.adform.com/ [Visit us!] Follow: [twitter]http://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Ross Black [mailto:ross.w.bl...@gmail.com] Sent: Friday, March 23, 2012 07:16 To: user@cassandra.apache.org Subject: Re: tombstones problem with 1.0.8 Hi Victor, Thanks for your response. Is there a possibility that continual deletions during compact could be blocking removal of the tombstones? The full manual compact takes about 4 hours per node for our data, so there is a large number of deletes occurring during that time. This is the description from cassandra-cli Replication Strategy: org.apache.cassandra.locator.SimpleStrategy Durable Writes: true Options: [replication_factor:3] Column Families: ColumnFamily: weekly Key Validation Class: org.apache.cassandra.db.marshal.BytesType Default column value validator: org.apache.cassandra.db.marshal.BytesType Columns sorted by: org.apache.cassandra.db.marshal.BytesType Row cache size / save period in seconds / keys to save : 0.0/0/all Row Cache Provider: org.apache.cassandra.cache.SerializingCacheProvider Key cache size / save period in seconds: 20.0/14400 GC grace seconds: 3600 Compaction min/max thresholds: 3/8 Read repair chance: 1.0 Replicate on write: true Bloom Filter FP chance: default Built indexes: [] Compaction Strategy: org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy Ross On 23 March 2012 02:55, Viktor Jevdokimov viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com wrote: Just tested 1.0.8 before upgrading from 1.0.7: tombstones created by TTL or by delete operation are perfectly deleted after either compaction or cleanup. Have no idea about any other settings than gc_grace_seconds, check you schema from cassandra-cli. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063tel:%2B370%205%20212%203063. Fax: +370 5 261 0453tel:%2B370%205%20261%200453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news]http://www.adform.com/ [Visit us!] Follow: [twitter]http://twitter.com/#%21/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Ross Black [mailto:ross.w.bl...@gmail.commailto:ross.w.bl...@gmail.com] Sent: Thursday, March 22, 2012 03:38 To: user@cassandra.apache.orgmailto:user@cassandra.apache.org Subject: tombstones problem with 1.0.8 Hi, We recently moved from 0.8.2 to 1.0.8 and the behaviour seems to have changed so that tombstones are now not being deleted. Our application continually adds and removes columns from Cassandra. We have set a short gc_grace time (3600) since our application would automatically delete zombies if they appear. Under 0.8.2, the tombstones remained at a relatively constant number. Under 1.0.8, the tombstones have been continually increasing so that they exceed the size of our real data (at this stage we have over 100G of tombstones). Even after running a full compact the new compacted SSTable contains a massive number of tombstones, many that are several weeks old. Have I missed some new configuration option to allow deletion of tombstones? I also noticed that one of the changes between 0.8.2
RE: tombstones problem with 1.0.8
You are explaining that if i have expired row tombstone and there exists later timestamp on this row that tombstone is not deleted? If this works that way, it will be never deleted. Exactly. It is merged with new one. Example 1: a row with 1 column in sstable. delete a row, not a column. after compaction or cleanup in sstable will exist an empty row key with tombstone. Example 2: a row with 1 column in sstable. delete a column. after compaction or cleanup in sstable will exist a row with 1 column with tombstone. Question: why delete operation is requested from application for a row/column that is already deleted (can't be returned by get)? Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063. Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania [Adform news]http://www.adform.com/ [Visit us!] Follow: [twitter]http://twitter.com/#!/adforminsider Visit our bloghttp://www.adform.com/site/blog Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. inline: signature-logo31e4.pnginline: dm-exco16d5.pnginline: tweet3564.png
RE: tombstones problem with 1.0.8
Should not. Scenario 1, write delete in one memtable T1 write column T2 delete row T3 flush memtable, sstable 1 contains empty row tombstone T4 row tombstone expires T5 compaction/cleanup, row disappears from sstable 2 Scenario 2, write delete different sstables T1 write column T2 flush memtable, sstable 1 contains row with column T3 delete row T4 flush memtable, sstable 2 contains empty row tombstone T5 row tombstone expires T6 compaction, rows from sstable 1 2 merged, not saved to sstable 3 Scenario 3, alive tombstone T1 write column T2 flush memtable, sstable 1 contains row with column T3 delete row T4 flush memtable, sstable 2 contains empty row tombstone T5 delete row (present in memtable) T6 row tombstone for T3 expected to be expired T7 compaction, sstable 3 row tombstone appears because of T5 Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.-Original Message- From: Radim Kolar [mailto:h...@filez.com] Sent: Friday, March 23, 2012 13:28 To: user@cassandra.apache.org Subject: Re: tombstones problem with 1.0.8 Example: T1 T2 T3 at T1 write column at T2 delete row at T3 tombstone expiration do compact ( T1 + T2 ) and drop expired tombstone column from T1 will be alive again?
RE: tombstones problem with 1.0.8
Upon read from S1 S6 rows are merged, T3 timestamp wins. T1 will be deleted upon S1 compaction with S6 or manual cleanup. We're running major compactions nightly, a lot of inserts per day with TTL, some with deletes from app - no problems with tombstones. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.-Original Message- From: Radim Kolar [mailto:h...@filez.com] Sent: Sunday, March 25, 2012 13:20 To: user@cassandra.apache.org Subject: Re: tombstones problem with 1.0.8 Scenario 4 T1 write column T2 Flush memtable to S1 T3 del row T4 flush memtable to S5 T5 tomstone S5 expires T6 S5 is compacted but not with S1 Result?
RE: size tiered compaction - improvement
Our use case requires Column TTL, not CF TTL, because it is variable, not constant. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.-Original Message- From: Radim Kolar [mailto:h...@filez.com] Sent: Wednesday, April 18, 2012 12:57 To: user@cassandra.apache.org Subject: Re: size tiered compaction - improvement Any compaction pass over A will first convert the TTL data into tombstones. Then, any subsequent pass that includes A *and all other sstables containing rows with the same key* will drop the tombstones. thats why i proposed to attach TTL to entire CF. Tombstones would not be needed
RE: zabbix templates
This is, for example, Zabbix agent config for Linux based Cassandra, just find
cmdline-jmxclient-0.10.3.jar. Not all items are there, add any you need, if
missed. Start from JMX to understand, what parameters to use with keys, for
example,
cassandra.db.Caches[KEYSPACE,CACHE_NAME,COUNTER]
### CASSANDRA USER-DEFINED MONITORED PARAMETERS
UserParameter=cassandra.db.Caches[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199
org.apache.cassandra.db:type=Caches,keyspace=$1,cache=$2 $3 21 | awk '{print
$$6;}'
UserParameter=cassandra.db.ColumnFamilies[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199
org.apache.cassandra.db:type=ColumnFamilies,keyspace=$1,columnfamily=$2 $3 21
| awk '{print $$6;}'
UserParameter=cassandra.db.CompactionManager[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199
org.apache.cassandra.db:type=CompactionManager $1 21 | awk '{print $$6;}'
UserParameter=cassandra.db.StorageProxy[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199
org.apache.cassandra.db:type=StorageProxy $1 21 | awk '{print $$6;}'
UserParameter=cassandra.db.StorageService[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199
org.apache.cassandra.db:type=StorageService $1 21 | awk
'{split($$6,a,E);if(a[2]!=){split(a[1],c,.);b=c[1]c[2];for(i=1;i=a[2]-length(c[2]);i++)b=b0;}
else b=a[1];print b;}'
UserParameter=cassandra.memory.Heap[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199 java.lang:type=Memory
HeapMemoryUsage 21 | awk '/$1/ {print $$2;}'
UserParameter=cassandra.memory.NonHeap[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199 java.lang:type=Memory
NonHeapMemoryUsage 21 | awk '/$1/ {print $$2;}'
UserParameter=cassandra.request.MutationStage[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199
org.apache.cassandra.request:type=MutationStage $1 21 | awk '{print $$6;}'
UserParameter=cassandra.request.ReadRepairStage[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199
org.apache.cassandra.request:type=ReadRepairStage $1 21 | awk '{print $$6;}'
UserParameter=cassandra.request.ReadStage[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199
org.apache.cassandra.request:type=ReadStage $1 21 | awk '{print $$6;}'
UserParameter=cassandra.request.RequestResponseStage[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199
org.apache.cassandra.request:type=MutationStage $1 21 | awk '{print $$6;}'
UserParameter=cassandra.runtime[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199
java.lang:type=Runtime $1 21 | awk '{print $$6;}'
UserParameter=cassandra.threading[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199
java.lang:type=Threading $1 21 | awk '{print $$6;}'
UserParameter=cassandra.os[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199
java.lang:type=OperatingSystem $1 21 | awk '{print $$6;}'
UserParameter=cassandra.gc.parnew[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199
java.lang:type=GarbageCollector,name=ParNew LastGcInfo 21 | awk '/$1/ {print
$$2;}'
UserParameter=cassandra.gc.cms[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199
java.lang:type=GarbageCollector,name=ConcurrentMarkSweep LastGcInfo 21 | awk
'/$1/ {print $$2;}'
UserParameter=cassandra.db.DynamicSnitchScores[*],java -jar
/etc/zabbix/cmdline-jmxclient-0.10.3.jar - 127.0.0.1:7199
org.apache.cassandra.db:type=DynamicEndpointSnitch,instance=* Scores 21 | awk
'{split($$0,a, );for(i in
a){if(match(a[i],/$1/)!=0){split(a[i],b,=);sub(/,|}/,,b[2]);print
b[2];break;}}}'
Best regards / Pagarbiai
Viktor Jevdokimov
Senior Developer
Email: viktor.jevdoki...@adform.com
Phone: +370 5 212 3063
Fax: +370 5 261 0453
J. Jasinskio 16C,
LT-01112 Vilnius,
Lithuania
Disclaimer: The information contained in this message and attachments is
intended solely for the attention and use of the named addressee and may be
confidential. If you are not the intended recipient, you are reminded that the
information remains the property of the sender. You must not use, disclose,
distribute, copy, print or rely on this e-mail. If you have received this
message in error, please contact the sender immediately and irrevocably delete
this message and any copies.-Original Message-
From: Cord MacLeod [mailto:cordmacl...@gmail.com]
Sent: Saturday, May 12, 2012 06:42
To: user@cassandra.apache.org
Subject: zabbix templates
I've seen some Cacti templates for Cassandra and a JMX bridge called zap cat,
but has anyone created Zabbix templates for Cassandra?
cassandra.conf
Description: cassandra.conf
RE: how to upgrade my cassadra from SizeTieredCompaction to LeveledCompactiom
There is 2T data on each server. Can someone give me some advice? do not do it Best advice! Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.
RE: counter CF and TTL
There's no TTL on counter columns and no ready-to-use solution I know about. https://issues.apache.org/jira/browse/CASSANDRA-2774 Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Tamar Fraenkel [mailto:ta...@tok-media.com] Sent: Sunday, May 13, 2012 18:30 To: cassandra-u...@incubator.apache.org Subject: counter CF and TTL Hi! I saw that when Counter CF were first introduced there was no support for TTL. But I see that Hector does have TTL for HCounterColumn So does a counter column have TTL or not? I actually don't have an issue of big rows, but I don't need the data after a two weeks or so, so it seems a shame to clutter the DB with it. Thanks, Tamar Fraenkel Senior Software Engineer, TOK Media [Inline image 1] ta...@tok-media.commailto:ta...@tok-media.com Tel: +972 2 6409736 Mob: +972 54 8356490 Fax: +972 2 5612956 inline: image001.pnginline: signature-logo29.png
RE: get dinamicsnith info from php
I'm not sure, that selecting node upon DS is a good idea. First of all every node has values about every node, including self. Self DS values are always better than others. For example, 3 nodes RF=2: N1 N2 N3 N1 0.5ms 2ms 2ms N2 2ms 0.5ms 2ms N3 2ms 2ms 0.5ms We have monitored many Cassandra counters, including DS values for every node, and graphs shows that latencies is not about load. So the strategy should be based on use case, node count, RF, replica placement strategy, read repair chance, and more, and more... What do you want to achieve? Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: ruslan usifov [mailto:ruslan.usi...@gmail.com] Sent: Monday, May 14, 2012 16:58 To: user@cassandra.apache.org Subject: get dinamicsnith info from php Hello I want to route request from php client to minimaly loaded node, so i need dinamicsnitch info and gosip, how can i get this info fro php. Perhaps need some daemon that can communicate with cassandra gosip and translate this info to php (socket for example)??? inline: signature-logo29.png
RE: get dinamicsnith info from php
Let say you have 8 nodes cluster with replication factor 3. If one node is down, for its token range you have only 2 nodes left, not 7, which can process you requests - other nodes will forward requests to the nearest (depends on snitch) or with lower latency (depends on dynamic snitch) of 2 remaining. I have no idea about PHP and its multithreading capabilities, if it's impossible to run background thread to return dead endpoint to the list, instead of checking it on HTTP request thread, you're stacked. For the lower latencies dynamic snitch already do a job for you, selecting a node with lower latencies. If you'd like Cassandra to avoid forwarding requests to appropriate node, but making a direct request to a node where data is, you need smarter client, capable to select node by key and other things to do to achieve this. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: ruslan usifov [mailto:ruslan.usi...@gmail.com] Sent: Monday, May 14, 2012 17:41 To: user@cassandra.apache.org Subject: Re: get dinamicsnith info from php Sorry for my bad english. I want to solve follow problem. For example we down one node for maintenance reason, for a long time (30 min). Now we use TSocketPool for polling connection to cassandra, but this poll implementation is as i think not so good, it have a custom parameter setRetryInterval, with allow off broken node (now we set i to 10sec), but this mean that every 10sec pool will try to connet down node (i repeat we shutdown node for maintance reason), because it doesn't know node dead or node, but cassandra cluster know this, and this connection attempt is senselessly, also when node make compact it can be heavy loaded, and can't serve client reqest very good (at this moment we can got little increase of avg backend responce time) 2012/5/14 Viktor Jevdokimov viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com I'm not sure, that selecting node upon DS is a good idea. First of all every node has values about every node, including self. Self DS values are always better than others. For example, 3 nodes RF=2: N1 N2 N3 N1 0.5ms 2ms 2ms N2 2ms 0.5ms 2ms N3 2ms 2ms 0.5ms We have monitored many Cassandra counters, including DS values for every node, and graphs shows that latencies is not about load. So the strategy should be based on use case, node count, RF, replica placement strategy, read repair chance, and more, and more... What do you want to achieve? Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#%21/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News]http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: ruslan usifov [mailto:ruslan.usi...@gmail.commailto:ruslan.usi...@gmail.com] Sent: Monday, May 14, 2012 16:58 To: user@cassandra.apache.orgmailto:user@cassandra.apache.org Subject: get dinamicsnith info from php Hello I want to route request from php client to minimaly loaded node, so i need dinamicsnitch info and gosip, how can i get this info fro php. Perhaps need some daemon that can communicate with cassandra gosip and translate this info to php (socket for example)??? inline: image001.pnginline: signature-logo29.png
RE: cassandra read latency help
Gurpreet Singh wrote: Any ideas on what could help here bring down the read latency even more ? Avoid Cassandra forwarding request to other nodes: - Use consistency level ONE; - Create data model to do single request with single key, since different keys may belong to different nodes and requires forwarding requests to them; - Use smart client to calculate token for key and select appropriate node (primary or replica) by token range; - Turn off Dynamic Snitch (it may forward request to other replica even it has the data); - Have all or hot data in page cache (no HDD disk IO) or use SSD; - If you do regular updates to key, do not use row cache, otherwise you may try. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.
RE: Exception when truncate
Truncate flushes all memtables to free up commit logs, and that on all nodes. So this takes time. Discussed on this list not so long ago. Watch for: https://issues.apache.org/jira/browse/CASSANDRA-3651 https://issues.apache.org/jira/browse/CASSANDRA-4006 Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. -Original Message- From: ruslan usifov [mailto:ruslan.usi...@gmail.com] Sent: Thursday, May 17, 2012 13:06 To: user@cassandra.apache.org Subject: Re: Exception when truncate Also i miss understand why on empty CF(no any SStable) truncate heavy loads disk?? 2012/5/17 ruslan usifov ruslan.usi...@gmail.com: Hello I have follow situation on our test server: from cassandra-cli i try to use truncate purchase_history; 3 times i got: [default@township_6waves] truncate purchase_history; null UnavailableException() at org.apache.cassandra.thrift.Cassandra$truncate_result.read(Cassandra.j ava:20212) at org.apache.cassandra.thrift.Cassandra$Client.recv_truncate(Cassandra.j ava:1077) at org.apache.cassandra.thrift.Cassandra$Client.truncate(Cassandra.java:1 052) at org.apache.cassandra.cli.CliClient.executeTruncate(CliClient.java:1445 ) at org.apache.cassandra.cli.CliClient.executeCLIStatement(CliClient.java: 272) at org.apache.cassandra.cli.CliMain.processStatementInteractive(CliMain.j ava:220) at org.apache.cassandra.cli.CliMain.main(CliMain.java:348) So this looks that truncate goes very slow and too long, than rpc_timeout_in_ms: 1 (this can happens because we have very slow disck on test machine) But in in cassandra system log i see follow exception: ERROR [MutationStage:7022] 2012-05-17 12:19:14,356 AbstractCassandraDaemon.java (line 139) Fatal exception in thread Thread[MutationStage:7022,5,main] java.io.IOError: java.io.IOException: unable to mkdirs /home/cassandra/1.0.0/data/township_6waves/snapshots/1337242754356- pur chase_history at org.apache.cassandra.db.ColumnFamilyStore.snapshotWithoutFlush(Column F amilyStore.java:1433) at org.apache.cassandra.db.ColumnFamilyStore.snapshot(ColumnFamilyStore.j ava:1462) at org.apache.cassandra.db.ColumnFamilyStore.truncate(ColumnFamilyStore.j ava:1657) at org.apache.cassandra.db.TruncateVerbHandler.doVerb(TruncateVerbHandle r .java:50) at org.apache.cassandra.net.MessageDeliveryTask.run(MessageDeliveryTask.j ava:59) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecu tor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor. java:908) at java.lang.Thread.run(Thread.java:662) Caused by: java.io.IOException: unable to mkdirs /home/cassandra/1.0.0/data/township_6waves/snapshots/1337242754356- pur chase_history at org.apache.cassandra.io.util.FileUtils.createDirectory(FileUtils.java: 140) at org.apache.cassandra.io.util.FileUtils.createDirectory(FileUtils.java: 131) at org.apache.cassandra.db.ColumnFamilyStore.snapshotWithoutFlush(Column F amilyStore.java:1409) ... 7 more Also i see that in snapshort dir already exists 1337242754356-purchase_history directory, so i think that snapshort names that generate cassandra not uniquely. PS: We use cassandra 1.0.10 on Ubuntu 10.0.4-LTS
RE: cassandra read latency help
Row cache is ok until keys are not heavily updated, otherwise it frequently invalidates and pressures GC. The high latency is from your batch of 100 keys. Review your data model to avoid such reads, if you need low latency. 500M rows on one node, or on the cluster? Reading 100 random rows at total of 40KB data from a data set of 180GB uncompressed under 30ms is not an easy task. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Gurpreet Singh [mailto:gurpreet.si...@gmail.com] Sent: Thursday, May 17, 2012 20:24 To: user@cassandra.apache.org Subject: Re: cassandra read latency help Thanks Viktor for the advice. Right now, i just have 1 node that i am testing against and i am using CL one. Are you suggesting that the page cache might be doing better than the row cache? I am getting row cache hit of 0.66 right now. /G On Thu, May 17, 2012 at 12:26 AM, Viktor Jevdokimov viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com wrote: Gurpreet Singh wrote: Any ideas on what could help here bring down the read latency even more ? Avoid Cassandra forwarding request to other nodes: - Use consistency level ONE; - Create data model to do single request with single key, since different keys may belong to different nodes and requires forwarding requests to them; - Use smart client to calculate token for key and select appropriate node (primary or replica) by token range; - Turn off Dynamic Snitch (it may forward request to other replica even it has the data); - Have all or hot data in page cache (no HDD disk IO) or use SSD; - If you do regular updates to key, do not use row cache, otherwise you may try. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063tel:%2B370%205%20212%203063 Fax: +370 5 261 0453tel:%2B370%205%20261%200453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. inline: signature-logo29.png
RE: Safely Disabling Compaction
To temporarily turn off compactions without schema update, use nodetool –h node_ip -p port setcompactionthreshold keyspace cfname minthreshold maxthreshold for every node and every column family you need. If nodetool throws same exception, do in 2 steps: 1. nodetool setcompactionthreshold keyspace cfname 0 32 (32 – use yours instead) 2. nodetool setcompactionthreshold keyspace cfname 0 0 To restore, set your normal values. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Vijay [mailto:vijay2...@gmail.com] Sent: Friday, May 18, 2012 06:09 To: user@cassandra.apache.org Cc: cassandra-u...@incubator.apache.org Subject: Re: Safely Disabling Compaction I would rather set the Keyspace setting min_compaction_threshold and max_compaction_threshold to be a higher number and once i am ready i will put the value back... This way i dont need to restart. Having said that why not set the compaction throughput to 1 (low enough to not have contention) and complete the stream? Regards, /VJ On Wed, May 16, 2012 at 2:43 PM, sj.climber sj.clim...@gmail.commailto:sj.clim...@gmail.com wrote: Hi, In an effort to minimize IO contention, I'd like to disable compactions while I'm streaming SSTables to the cluster. When done streaming, I intend on forcing a major compaction through nodetool. Elsewhere in the forums, various folks suggest setting max_compaction_threshold = 0 to disable compaction. While this works sometimes (via 'update column family family with max_compaction_threshold=0'), I've observed a number of serious issues with this approach: 1) You can't create a column family with max_compaction_threshold = 0. The CLI reports that min_compaction_threshold must have a value = 2, and max_compaction_threshold can't be lower than it. Worse yet, trying to create a column family with max_compaction_threshold = 0 gets the cluster into a Schema Disagreement Exception (since the node on which you issue the migration command fails with a fatal error). 2) Cassandra will allow me to update an existing column family with max_compaction_threshold = 0. But if I restart the node, it will crash on startup. java.lang.reflect.InvocationTargetException at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.apache.commons.daemon.support.DaemonLoader.load(DaemonLoader.java:160) Caused by: java.lang.RuntimeException: java.lang.reflect.InvocationTargetException ... org.apache.cassandra.config.CFMetaData.createCompactionStrategyInstance(CFMetaData.java:839) ... 14 more Caused by: java.lang.RuntimeException: The max_compaction_threshold cannot be smaller than the min. at org.apache.cassandra.db.ColumnFamilyStore.setMaximumCompactionThreshold(ColumnFamilyStore.java:1740) at org.apache. Is there another solution for more safely enabling/disabling compaction? Thanks! -- View this message in context: http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/Safely-Disabling-Compaction-tp7562777.html Sent from the cassandra-u...@incubator.apache.orgmailto:cassandra-u...@incubator.apache.org mailing list archive at Nabble.com. inline: signature-logo29.png
RE: Replication factor
When RF == number of nodes, and you read at CL ONE you will always be reading locally. always be reading locally - only if Dynamic Snitch is off. With dynamic snitch on request may be redirected to other node, which may introduce latency spikes. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: aaron morton [mailto:aa...@thelastpickle.com] Sent: Wednesday, May 23, 2012 13:00 To: user@cassandra.apache.org Subject: Re: Replication factor RF is normally adjusted to modify availability (see http://thelastpickle.com/2011/06/13/Down-For-Me/) for example, if I have 4 nodes cluster in one data center, how can RF=2 vs RF=4 affect read performance? If consistency level is ONE, looks reading does not need to go to another hop to get data if RF=4, but it would do more work on read repair in the background. Read Repair does not run at CL ONE. When RF == number of nodes, and you read at CL ONE you will always be reading locally. But with a low consistency. If you read with QUORUM when RF == number of nodes you will still get some performance benefit from the data being read locally. Cheers - Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 23/05/2012, at 9:34 AM, Daning Wang wrote: Hello, What is the pros and cons to choose different number of replication factor in term of performance? if space is not a concern. for example, if I have 4 nodes cluster in one data center, how can RF=2 vs RF=4 affect read performance? If consistency level is ONE, looks reading does not need to go to another hop to get data if RF=4, but it would do more work on read repair in the background. Can you share some insights about this? Thanks in advance, Daning inline: signature-logo7789.png
RE: Replication factor
Depends on use case. For ours we have another experience and statistics, when turning dynamic snitch off makes overall latency and spikes much, much lower. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Brandon Williams [mailto:dri...@gmail.com] Sent: Thursday, May 24, 2012 02:35 To: user@cassandra.apache.org Subject: Re: Replication factor On Wed, May 23, 2012 at 5:51 AM, Viktor Jevdokimov viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com wrote: When RF == number of nodes, and you read at CL ONE you will always be reading locally. always be reading locally - only if Dynamic Snitch is off. With dynamic snitch on request may be redirected to other node, which may introduce latency spikes. Actually it's preventing spikes, since if it won't read locally that means the local replica is in worse shape than the rest (compacting, repairing, etc.) -Brandon inline: signature-logo29.png
RE: Replication factor
All data is in the page cache. No repairs. Compactions not hitting disk for read. CPU 50%. ParNew GC 100 ms in average. After one compaction completes, new sstable is not in page cache, there may be a disk usage spike before data is cached, so local reads gets slower for a moment, comparing with other nodes. Redirecting almost all requests to other nodes finally ends up with a huge latency spike almost on all nodes, especially when ParNew GC may spike on one node (200ms). We call it cluster hiccup, when incoming and outgoing network traffic drops for a moment. And such hiccups happens several times an hour, few seconds long. Playing with badness threshold did not gave a lot better results, but turning DS off completely fixed all problems with latencies, node spikes, cluster hiccups and network traffic drops. In our case, our client is selecting endpoints for a key by calculating a token, so we always hit a replica. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: aaron morton [mailto:aa...@thelastpickle.com] Sent: Thursday, May 24, 2012 13:00 To: user@cassandra.apache.org Subject: Re: Replication factor Your experience is when using CL ONE the Dynamic Snitch is moving local reads off to other nodes and this is causing spikes in read latency ? Did you notice what was happening on the node for the DS to think it was so slow ? Was compaction or repair going on ? Have you played with the badness threshold https://github.com/apache/cassandra/blob/trunk/conf/cassandra.yaml#L472 ? Cheers - Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 24/05/2012, at 5:28 PM, Viktor Jevdokimov wrote: Depends on use case. For ours we have another experience and statistics, when turning dynamic snitch off makes overall latency and spikes much, much lower. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display signature-logo29.pnghttp://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Brandon Williams [mailto:dri...@gmail.com]mailto:[mailto:dri...@gmail.com] Sent: Thursday, May 24, 2012 02:35 To: user@cassandra.apache.orgmailto:user@cassandra.apache.org Subject: Re: Replication factor On Wed, May 23, 2012 at 5:51 AM, Viktor Jevdokimov viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com wrote: When RF == number of nodes, and you read at CL ONE you will always be reading locally. always be reading locally - only if Dynamic Snitch is off. With dynamic snitch on request may be redirected to other node, which may introduce latency spikes. Actually it's preventing spikes, since if it won't read locally that means the local replica is in worse shape than the rest (compacting, repairing, etc.) -Brandon inline: signature-logo18be.png
FYI: Java 7u4 on Linux requires higher stack size
Hell all, We've started to test Oracle Java 7u4 (currently we're on 7u3) on Linux to try G1 GC. Cassandra can't start on 7u4 with exception: The stack size specified is too small, Specify at least 160k Cannot create Java VM Changing in cassandra-env.sh -Xss128k to -Xss160k allowed to start Cassandra, but when Thrift client disconnects, Cassandra log fills with exceptions: ERROR 17:08:56,300 Fatal exception in thread Thread[Thrift:13,5,main] java.lang.StackOverflowError at java.net.SocketInputStream.socketRead0(Native Method) at java.net.SocketInputStream.read(Unknown Source) at java.net.SocketInputStream.read(Unknown Source) at java.io.BufferedInputStream.fill(Unknown Source) at java.io.BufferedInputStream.read1(Unknown Source) at java.io.BufferedInputStream.read(Unknown Source) at org.apache.thrift.transport.TIOStreamTransport.read(TIOStreamTransport.java:127) at org.apache.thrift.transport.TTransport.readAll(TTransport.java:84) at org.apache.thrift.transport.TFramedTransport.readFrame(TFramedTransport.java:129) at org.apache.thrift.transport.TFramedTransport.read(TFramedTransport.java:101) at org.apache.thrift.transport.TTransport.readAll(TTransport.java:84) at org.apache.thrift.protocol.TBinaryProtocol.readAll(TBinaryProtocol.java:378) at org.apache.thrift.protocol.TBinaryProtocol.readI32(TBinaryProtocol.java:297) at org.apache.thrift.protocol.TBinaryProtocol.readMessageBegin(TBinaryProtocol.java:204) at org.apache.cassandra.thrift.Cassandra$Processor.process(Cassandra.java:2877) at org.apache.cassandra.thrift.CustomTThreadPoolServer$WorkerProcess.run(CustomTThreadPoolServer.java:187) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source) Increasing stack size from 160k to 192k eliminated such excepitons. Just wanted you to know if someone tries to migrate to Java 7u4. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. inline: signature-logo29.png
RE: repair
Why without -PR when recovering from crash? Repair without -PR runs full repair of the cluster, the node which receives a command is a repair controller, ALL nodes synchronizes replicas at the same time, streaming data between each other. The problems may arise: · When streaming hangs (it tends to hang even on a stable network), repair session hangs (any version does re-stream?) · Network will be highly saturated · In case of high inconsistency some nodes may receive a lot of data, disk usage much more than 2x (depends on RF) · A lot of compactions will be pending IMO, best way to run repair is from script with -PR for single CF from single node at a time and monitoring progress, like: repair -pr node1 ks1 cf1 repair -pr node2 ks1 cf1 repair -pr node3 ks1 cf1 repair -pr node1 ks1 cf2 repair -pr node2 ks1 cf2 repair -pr node3 ks1 cf2 With some progress or other control in between, your choice. Use repair with care, do not let your cluster go down. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: R. Verlangen [mailto:ro...@us2.nl] Sent: Monday, June 04, 2012 15:17 To: user@cassandra.apache.org Subject: Re: repair The repair -pr only repairs the nodes primary range: so is only usefull in day to day use. When you're recovering from a crash use it without -pr. 2012/6/4 Romain HARDOUIN romain.hardo...@urssaf.frmailto:romain.hardo...@urssaf.fr Run repair -pr in your cron. Tamar Fraenkel ta...@tok-media.commailto:ta...@tok-media.com a écrit sur 04/06/2012 13:44:32 : Thanks. I actually did just that with cron jobs running on different hours. I asked the question because I saw that when one of the logs was running the repair, all nodes logged some repair related entries in /var/log/cassandra/system.log Thanks again, Tamar Fraenkel Senior Software Engineer, TOK Media -- With kind regards, Robin Verlangen Software engineer W www.robinverlangen.nlhttp://www.robinverlangen.nl E ro...@us2.nlmailto:ro...@us2.nl Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. inline: signature-logo29.png
RE: nodetool repair -pr enough in this scenario?
Understand simple mechanics first, decide how to act later. Without -PR there's no difference from which host to run repair, it runs for the whole 100% range, from start to end, the whole cluster, all nodes, at once. With -PR it runs only for a primary range of a node you are running a repair. Let say you have simple ring of 3 nodes with RF=2 and ranges (per node) N1=C-A, N2=A-B, N3=B-C (node tokens are N1=A, N2=B, N3=C). No rack, no DC aware. So running repair with -PR on node N2 will only repair a range A-B, for which node N2 is a primary and N3 is a backup. N2 and N3 will synchronize A-B range one with other. For other ranges you need to run on other nodes. Without -PR running on any node will repair all ranges, A-B, B-C, C-A. A node you run a repair without -PR is just a repair coordinator, so no difference, which one will be next time. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: David Daeschler [mailto:david.daesch...@gmail.com] Sent: Tuesday, June 05, 2012 08:59 To: user@cassandra.apache.org Subject: nodetool repair -pr enough in this scenario? Hello, Currently I have a 4 node cassandra cluster on CentOS64. I have been running nodetool repair (no -pr option) on a weekly schedule like: Host1: Tue, Host2: Wed, Host3: Thu, Host4: Fri In this scenario, if I were to add the -pr option, would this still be sufficient to prevent forgotten deletes and properly maintain consistency? Thank you, - David inline: signature-logo29.png
RE: nodetool repair -pr enough in this scenario?
But in any case, repair is a two way process? I mean that repair without -PR on node N1 will repair N1 and N2 and N3, because N2 is a replica of N1 range and N1 is a replica of N3 range? And if there're more ranges, that not belongs to N1, that ranges and nodes will not be repaired? Am I understood correctly, that repair with or without -PR is not a repair selected node process, but synchronize data range(s) between replicas process? Single DC scenario: With -PR: synchronize data for only primary data range of selected node between all nodes for that range (max number of nodes for the range = RF). Without -PR: synchronize data for all data ranges of selected node (primary and replica) between all nodes of that ranges (max number of nodes for the ranges = RF*RF). Not effective since ranges overlaps, the same ranges will be synchronized more than once (max = RF times). Multiple DC with 100% data range in each DC scenario: the same, only RF = sum of RF from all DC's. Is that correct? Finally - is this process for SSTables only, excluding memtables and hints? Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Sylvain Lebresne [mailto:sylv...@datastax.com] Sent: Tuesday, June 05, 2012 11:02 To: user@cassandra.apache.org Subject: Re: nodetool repair -pr enough in this scenario? On Tue, Jun 5, 2012 at 8:44 AM, Viktor Jevdokimov viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com wrote: Understand simple mechanics first, decide how to act later. Without -PR there's no difference from which host to run repair, it runs for the whole 100% range, from start to end, the whole cluster, all nodes, at once. That's not exactly true. A repair without -pr will repair all the ranges of the node on which repair is ran. So it will only repair the ranges that the node is a replica for. It will *not* repair the whole cluster (unless the replication factor is equal to the number of nodes in the cluster but that's a degenerate case). And hence it does matter on which host repair is run (it always matter, whether you use -pr or not). In general you want to use repair without -pr in case where you want to repair a specific node. Typically, if a node was dead for a reasonably long time, you may want to run a repair (without -pr) on that specific node to have him catch up faster (faster that if you were only relying on read-repair and hinted-handoff). For repairing a whole cluster, as is the case for the weekly scheduled repairs in the initial question, you want to use -rp. You *do not* want to use repair without -pr in that case. You do not because for that task using -pr is more efficient (and to be clear, not using -pr won't cause problems, but it does is less efficient). -- Sylvain With -PR it runs only for a primary range of a node you are running a repair. Let say you have simple ring of 3 nodes with RF=2 and ranges (per node) N1=C-A, N2=A-B, N3=B-C (node tokens are N1=A, N2=B, N3=C). No rack, no DC aware. So running repair with -PR on node N2 will only repair a range A-B, for which node N2 is a primary and N3 is a backup. N2 and N3 will synchronize A-B range one with other. For other ranges you need to run on other nodes. Without -PR running on any node will repair all ranges, A-B, B-C, C-A. A node you run a repair without -PR is just a repair coordinator, so no difference, which one will be next time. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063tel:%2B370%205%20212%203063, Fax +370 5 261 0453tel:%2B370%205%20261%200453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News]http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must
RE: portability between enterprise and community version
Do not mix Linux and Windows nodes. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Abhijit Chanda [mailto:abhijit.chan...@gmail.com] Sent: Wednesday, June 13, 2012 09:21 To: user@cassandra.apache.org Subject: portability between enterprise and community version Hi All, Is it possible to communicate from a datastax enterprise edition to datastax community edition. Actually i want to set one of my node in linux box and other in windows. Please suggest. With Regards, -- Abhijit Chanda VeHere Interactive Pvt. Ltd. +91-974395 inline: signature-logo368b.png
RE: portability between enterprise and community version
Repair (streaming) will not work. Probably schema update will not work also, it was long time ago, don't remember. Migration of the cluster between Windows and Linux also not an easy task, a lot of manual work. Finally, mixed Cassandra environments are not supported as by DataStax as by anyone else. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Abhijit Chanda [mailto:abhijit.chan...@gmail.com] Sent: Wednesday, June 13, 2012 10:54 To: user@cassandra.apache.org Subject: Re: portability between enterprise and community version Hi Viktor Jevadokimov, May i know what are the issues i may face if i mix windows cluster along with linux cluster. Regards, -- Abhijit Chanda VeHere Interactive Pvt. Ltd. +91-974395 inline: signature-logo29.png
RE: portability between enterprise and community version
I remember that join and decommission didn’t worked since using streaming. All problems was due to paths differences between Windows and Linux styles. So how do you move keyspaces? Using streaming (join/decommission), or manually? Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Sasha Dolgy [mailto:sdo...@gmail.com] Sent: Wednesday, June 13, 2012 12:04 To: user@cassandra.apache.org Subject: Re: portability between enterprise and community version I consistently move keyspaces from linux machines onto windows machines for development purposes. I've had no issues ... but would probably be hesitant in rolling this out into a productive instance. Depends on the level of risk you want to take. : ) Run some tests ... mix things up and share your experiences ... Personally, I could see some value in not really caring what OS my cassandra instances are running on ... just that the JVM's are consistent and the available hardware resources are sufficient I don't speak for the vendors mentioned in this thread, but traditionally, the first step towards supportability is finding the problems / identifying the risks and see if they can be resolved ... -sd On Wed, Jun 13, 2012 at 10:26 AM, Viktor Jevdokimov viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com wrote: Repair (streaming) will not work. Probably schema update will not work also, it was long time ago, don’t remember. Migration of the cluster between Windows and Linux also not an easy task, a lot of manual work. Finally, mixed Cassandra environments are not supported as by DataStax as by anyone else. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063tel:%2B370%205%20212%203063, Fax +370 5 261 0453tel:%2B370%205%20261%200453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#%21/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News]http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Abhijit Chanda [mailto:abhijit.chan...@gmail.commailto:abhijit.chan...@gmail.com] Sent: Wednesday, June 13, 2012 10:54 To: user@cassandra.apache.orgmailto:user@cassandra.apache.org Subject: Re: portability between enterprise and community version Hi Viktor Jevadokimov, May i know what are the issues i may face if i mix windows cluster along with linux cluster. inline: image001.pnginline: signature-logo2149.png
RE: portability between enterprise and community version
Clients are clients, servers are servers. Why do you need mixed environment Cassandra cluster? Isn't enough mixed clients? Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Abhijit Chanda [mailto:abhijit.chan...@gmail.com] Sent: Wednesday, June 13, 2012 12:41 To: user@cassandra.apache.org Subject: Re: portability between enterprise and community version Hi Sasha, Viktor, In my case i have a project in which both java and .NET modules are there. For Java i m using Astyanax API and for .NET Fluent Cassandra. I am using DSE 2.1 for development purpose as i need partial searching in some of queries, which i m doing with the help of solr which is integrated in DSE latest versions. And this is working fine for all the Java modules, but i want the same for .NET modules also. Thats why i was looking for a mixed environment. Finally i want to ask whether i am moving in the right direction or not? please suggest. Thanks, -- Abhijit Chanda VeHere Interactive Pvt. Ltd. +91-974395 inline: signature-logo29.png
RE: cassandra 1.0.x and java 1.7
We use 7u3 in production long enough with no problems. 7u4 requires larger minimum stack size, 160KB vs 128KB, but 160KB still not enough for Cassandra, with 192KB better, but needs more testing. https://issues.apache.org/jira/browse/CASSANDRA-4275 suggests 256KB Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. -Original Message- From: ruslan usifov [mailto:ruslan.usi...@gmail.com] Sent: Monday, June 18, 2012 15:13 To: user@cassandra.apache.org Subject: cassandra 1.0.x and java 1.7 Hello! Is it safe to use java 1.7 with cassandra 1.0.x Reason why i want do that, is that in java 1.7 appear options for rotate GC log: http://bugs.sun.com/bugdatabase/view_bug.do;jsessionid=ff824681055961f fffe1f62393b68deb5?bug_id=6941923
RE: upgrade issue
Replace tabs with spaces in Cassandra.yaml Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Adeel Akbar [mailto:adeel.ak...@panasiangroup.com] Sent: Friday, June 29, 2012 12:53 To: user@cassandra.apache.org Subject: upgrade issue Hi, I have upgraded cassndra from 0.8.6 to 1.0.10 and found following errors once i started service; INFO 05:11:50,948 Logging initialized INFO 05:11:50,953 JVM vendor/version: OpenJDK 64-Bit Server VM/1.6.0_24 INFO 05:11:50,954 Heap size: 511705088/511705088 INFO 05:11:50,955 Classpath: /opt/apache-cassandra-1.0.10/bin/../conf:/opt/apache-cassandra-1.0.10/bin/../build/classes/main:/opt/apache-cassandra-1.0.10/bin/../build/classes/thrift:/opt/apache-cassandra-1.0.10/bin/../lib/antlr-3.2.jar:/opt/apache-cassandra-1.0.10/bin/../lib/apache-cassandra-1.0.10.jar:/opt/apache-cassandra-1.0.10/bin/../lib/apache-cassandra-clientutil-1.0.10.jar:/opt/apache-cassandra-1.0.10/bin/../lib/apache-cassandra-thrift-1.0.10.jar:/opt/apache-cassandra-1.0.10/bin/../lib/avro-1.4.0-fixes.jar:/opt/apache-cassandra-1.0.10/bin/../lib/avro-1.4.0-sources-fixes.jar:/opt/apache-cassandra-1.0.10/bin/../lib/commons-cli-1.1.jar:/opt/apache-cassandra-1.0.10/bin/../lib/commons-codec-1.2.jar:/opt/apache-cassandra-1.0.10/bin/../lib/commons-lang-2.4.jar:/opt/apache-cassandra-1.0.10/bin/../lib/compress-lzf-0.8.4.jar:/opt/apache-cassandra-1.0.10/bin/../lib/concurrentlinkedhashmap-lru-1.2.jar:/opt/apache-cassandra-1.0.10/bin/../lib/guava-r08.jar:/opt/apache-cassandra-1.0.10/bin/../lib/high-scale-lib-1.1.2.j ar:/opt/apache-cassandra-1.0.10/bin/../lib/jackson-core-asl-1.4.0.jar:/opt/apache-cassandra-1.0.10/bin/../lib/jackson-mapper-asl-1.4.0.jar:/opt/apache-cassandra-1.0.10/bin/../lib/jamm-0.2.5.jar:/opt/apache-cassandra-1.0.10/bin/../lib/jline-0.9.94.jar:/opt/apache-cassandra-1.0.10/bin/../lib/json-simple-1.1.jar:/opt/apache-cassandra-1.0.10/bin/../lib/libthrift-0.6.jar:/opt/apache-cassandra-1.0.10/bin/../lib/log4j-1.2.16.jar:/opt/apache-cassandra-1.0.10/bin/../lib/servlet-api-2.5-20081211.jar:/opt/apache-cassandra-1.0.10/bin/../lib/slf4j-api-1.6.1.jar:/opt/apache-cassandra-1.0.10/bin/../lib/slf4j-log4j12-1.6.1.jar:/opt/apache-cassandra-1.0.10/bin/../lib/snakeyaml-1.6.jar:/opt/apache-cassandra-1.0.10/bin/../lib/snappy-java-1.0.4.1.jar INFO 05:11:50,957 JNA not found. Native methods will be disabled. INFO 05:11:50,966 Loading settings from file:/opt/apache-cassandra-1.0.10/conf/cassandra.yamlfile:///\\opt\apache-cassandra-1.0.10\conf\cassandra.yaml ERROR 05:11:51,057 Fatal configuration error error while scanning for the next token found character '\t' that cannot start any token in reader, line 102, column 1: - seeds: 172.16.100.244,172. ... ^ at org.yaml.snakeyaml.scanner.ScannerImpl.fetchMoreTokens(ScannerImpl.java:357) at org.yaml.snakeyaml.scanner.ScannerImpl.checkToken(ScannerImpl.java:180) at org.yaml.snakeyaml.parser.ParserImpl$ParseBlockMappingValue.produce(ParserImpl.java:591) at org.yaml.snakeyaml.parser.ParserImpl.peekEvent(ParserImpl.java:162) at org.yaml.snakeyaml.parser.ParserImpl.checkEvent(ParserImpl.java:147) at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:131) at org.yaml.snakeyaml.composer.Composer.composeMappingNode(Composer.java:229) at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:159) at org.yaml.snakeyaml.composer.Composer.composeSequenceNode(Composer.java:203) at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:157) at org.yaml.snakeyaml.composer.Composer.composeMappingNode(Composer.java:229) at org.yaml.snakeyaml.composer.Composer.composeNode(Composer.java:159) at org.yaml.snakeyaml.composer.Composer.composeDocument(Composer.java:121) at org.yaml.snakeyaml.composer.Composer.getSingleNode(Composer.java:104) at org.yaml.snakeyaml.constructor.BaseConstructor.getSingleData(BaseConstructor.java:117) at org.yaml.snakeyaml.Loader.load(Loader.java:52) at org.yaml.snakeyaml.Yaml.load(Yaml.java:166
RE: Tools for analize cassandra gc.log
All of written below is my personal experience, as goals I wanted to achieve. We use these parameters in PROD for GC logs: JVM_OPTS=$JVM_OPTS -XX:+PrintGCTimeStamps JVM_OPTS=$JVM_OPTS -XX:+PrintGCDetails JVM_OPTS=$JVM_OPTS -Xloggc:/var/log/cassandra/gc-`date +%s`.log Log rotation works from Oracle Java 1.7.0_02: JVM_OPTS=$JVM_OPTS -XX:+UseGCLogFileRotation JVM_OPTS=$JVM_OPTS -XX:NumberOfGCLogFiles=10 JVM_OPTS=$JVM_OPTS -XX:GCLogFileSize=10M Adding other parameters may generate log not readable by many/any analyzer. Adding JVM_OPTS=$JVM_OPTS -XX:+PrintHeapAtGC will not break analizers below, but useful only to review manually. 1. GCHisto http://java.net/projects/gchisto/ - to load different logs and compare some numbers (pauses and number of GC's). Very useful for comparison. 2. GCViewer http://www.tagtraum.com/gcviewer.html - shows memory consumption and pauses stats and graphs. 3. PrintGCStats http://java.net/projects/printgcstats/ - text only, Linux only. 4. Garbagecat - a garbage, very little info, text only, while GCHisto GCViewer much more info and graphical. Considering what to play with, understand Java GC first: http://www.scribd.com/doc/37127094/GCTuningPresentationFISL10 http://developers.sun.com/mobility/midp/articles/garbagecollection2/ http://www.oracle.com/technetwork/java/javase/gc-tuning-6-140523.html Most objects taking time in GC pause: Memtables, Caches; other objects dying fast - cleaned, instead of copied/promoted. So play with memtable size also, cache invalidation. GC frequency will grow when compaction is running, but not pauses (very short living objects). Testing a lot of scenarios we found standard Cassandra GC settings are fine for most cases, you may need to play with max heap and young heap size. Other than that you may play with: -XX:+UseNUMA -XX:SurvivorRatio=8 (4-16) Not worth to play with: -XX:MaxTenuringThreshold=1 (0 or more than 1 is not a good thing) So mostly changing standard settings is a subject of achievement. Tuning GC is a last resort to gain something. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. -Original Message- From: ruslan usifov [mailto:ruslan.usi...@gmail.com] Sent: Wednesday, July 04, 2012 14:08 To: user@cassandra.apache.org Subject: Tools for analize cassandra gc.log Hello Please dear community share some tools for gc.log analize. I found http://code.google.com/a/eclipselabs.org/p/garbagecat/, but it doesn't work
RE: how to disable compression ?
First you update schema for CF, then you run nodetool upgradesstables on each node: nodetool -h [HOST] -p [JMXPORT] upgradesstables [keyspace] [cfnames] For me sometimes it works only after node restart (upgrade leaves previous format, compressed or uncompressed). Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Илья Шипицин [mailto:chipits...@gmail.com] Sent: Friday, July 20, 2012 10:16 To: user@cassandra.apache.org Subject: how to disable compression ? Hello! how can I run update command on column family to disable compression (without re-creating CF) ? Cheers, Ilya Shipitsin inline: signature-logo29.png
RE: how to disable compression ?
From cassandra-cli help:
To disable compression just set compression_options to null like this
compression_options = null
so
[default@XXXKeyspace] update column family YYY with compression_options = null;
Best regards / Pagarbiai
Viktor Jevdokimov
Senior Developer
Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com
Phone: +370 5 212 3063, Fax +370 5 261 0453
J. Jasinskio 16C, LT-01112 Vilnius, Lithuania
Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider
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Disclaimer: The information contained in this message and attachments is
intended solely for the attention and use of the named addressee and may be
confidential. If you are not the intended recipient, you are reminded that the
information remains the property of the sender. You must not use, disclose,
distribute, copy, print or rely on this e-mail. If you have received this
message in error, please contact the sender immediately and irrevocably delete
this message and any copies.
From: Илья Шипицин [mailto:chipits...@gmail.com]
Sent: Friday, July 20, 2012 10:37
To: user@cassandra.apache.org
Subject: Re: how to disable compression ?
[default@XXXKeyspace] update column family YYY with compression_options =[{}];
Command not found: `update column family YYY with compression_options =[{}];`.
Type 'help;' or '?' for help.
[default@XXXKeyspace]
2012/7/20 Viktor Jevdokimov
viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com
First you update schema for CF, then you run nodetool upgradesstables on each
node:
nodetool -h [HOST] -p [JMXPORT] upgradesstables [keyspace] [cfnames]
For me sometimes it works only after node restart (upgrade leaves previous
format, compressed or uncompressed).
Best regards / Pagarbiai
Viktor Jevdokimov
Senior Developer
Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com
Phone: +370 5 212 3063, Fax +370 5 261 0453
J. Jasinskio 16C, LT-01112 Vilnius, Lithuania
Follow us on Twitter: @adforminsiderhttp://twitter.com/#%21/adforminsider
What is Adform: watch this short videohttp://vimeo.com/adform/display
[Adform News]http://www.adform.com
Disclaimer: The information contained in this message and attachments is
intended solely for the attention and use of the named addressee and may be
confidential. If you are not the intended recipient, you are reminded that the
information remains the property of the sender. You must not use, disclose,
distribute, copy, print or rely on this e-mail. If you have received this
message in error, please contact the sender immediately and irrevocably delete
this message and any copies.
From: Илья Шипицин [mailto:chipits...@gmail.commailto:chipits...@gmail.com]
Sent: Friday, July 20, 2012 10:16
To: user@cassandra.apache.orgmailto:user@cassandra.apache.org
Subject: how to disable compression ?
Hello!
how can I run update command on column family to disable compression (without
re-creating CF) ?
Cheers,
Ilya Shipitsin
inline: image001.pnginline: signature-logo29.png
RE: Read latency skyrockets after 95-98th percentile
What is a data load? Does it fits in RAM? I bet it's due to GC. Since this is a 1 node only, dynamic snitch is out of scope. Best regards / Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com Phone: +370 5 212 3063, Fax +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Follow us on Twitter: @adforminsiderhttp://twitter.com/#!/adforminsider What is Adform: watch this short videohttp://vimeo.com/adform/display [Adform News] http://www.adform.com Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies. From: Andras Szerdahelyi [mailto:andras.szerdahe...@ignitionone.com] Sent: Tuesday, July 31, 2012 15:53 To: user@cassandra.apache.org Subject: Read latency skyrockets after 95-98th percentile hey list, i've been trying to understand why we are seeing rather nasty read latency peaks in as much as 2% of our total read ( not sure what the underlying thrift call is, should be get_slice ) requests that we have been **unable to tie to garbage collection or blocking I/O.** This is what i mean by nasty : Mean: 1.186341, Max: 41.912 stDev: 2.2490502737495333, 75th:1.02424999, 95th: 2.11034977, 98th: 5.21026034, 99th: 13.248351, 999th: 41.8945400041 This is measured around the Astyanax / Hector wrappers for running column slice queries and iterating over their results. FWIW they perform very similarly. Now, the mean is awesome - 1.2ms for a read is really really fast, i think thrift overhead makes up for probably 1ms alone. What i can't live with is pretty much everything thats beyond the 98th percentile. Perhaps my expectations are misaligned to begin with and this is great, but the dataset under test that yielded this result ( see below ) is extremely small - only a 1000 items per test made up of a few small dynamic composite columns and the read is being done sequentially, from a single threaded client. I just don't understand whats causing the peaks. Here's the complete run-down on the setup: The data is dynamic composite columns with string or integer values. The DynamicComposites themselves are made up of 3 Components each: String,String,Integer and String,Integer,Integer The query is getting all columns ( in this particular test, that will be a single column ) of one of the composite types ( String, String, Integer or String, Integer, Integer ) for a particular string key. ( How this is achieved is more or less at https://gist.github.com/3207894 ) The production cluster is set up as follows: 30-40 read/sec clients from multiple hosts, NetworkTopologyStrategy, 2 replicas per DC, read consistency: ONE, 2DCs, 2 nodes per DC ) 8GB multi-core physical hosts most settings on default in cassandra.yaml In an attempt to isolate the problem, i've done the following ( this is where the results above are coming from but we see roughly the same numbers in prod ) - created a short unit test around the ( two ) classes that wrap the Astyanax and Hector libraries in our application, in which i'm only testing the read performance - in setUp() i start Cassandra with CassandraStoreKeeperTest.cassandra = new CassandraDaemon(); CassandraStoreKeeperTest.cassandra.init(null); CassandraStoreKeeperTest.cassandra.start(); - same cassandra yaml as in prod, file at https://gist.github.com/3207894 ( mostly defaults ) - i pass the following flags to the JVM running my unit test: -server -Xmx2G and all the GC flags from cassandra-env.sh, plus the jamm java agent - i warm up the embedded cassandra with 1k reads and 1k writes - the test is 1000 single threaded, sequential reads via Hector and Astyanax ( no significant differences between the two ) via thrift to the embedded single-node Cassandra instance - i read back the 1000 items saved in the warm-up The results are Mean: 1.186341, Max: 41.912 stDev: 2.2490502737495333, 75th:1.02424999, 95th: 2.11034977, 98th: 5.21026034, 99th: 13.248351, 999th: 41.8945400041 here's the GC output during the read [GC [ParNew Desired survivor size 1081344 bytes, new threshold 1 (max 1) - age 1: 281480 bytes, 281480 total : 17322K-308K(19136K), 0.0037375 secs] 28742K-11885K(83008K), 0.0038170 secs] [Times: user=0.01 sys=0.00, real=0.01 secs] [GC [ParNew Desired survivor size 1081344 bytes, new threshold 1 (max 1) - age 1: 261360 bytes, 261360 total : 17332K-386K(19136K), 0.0034069 secs] 28909K-12098K(83008K), 0.0034849 secs] [Times: user=0.00 sys=0.01, real=0.00
RE: Preventing an update of a CF row
Nice and simple! -Original Message- From: Oleg Anastasyev [mailto:olega...@gmail.com] Sent: Tuesday, October 19, 2010 9:00 AM To: user@cassandra.apache.org Subject: Re: Preventing an update of a CF row kannan chandrasekaran ckannanck at yahoo.com writes: Hi All,I have a query regarding the insert operation. The insert operation by default inserts an new row or updates an existing row. Is it possible to prevent an update but allow only inserts automatically ( especially when multiple clients are writing to cassandra)? I was wondering if there is any flag in cassandra that will validate this for me automatically ( something like unique key constraint) ? If not, is it non-trivial to implement this ? Any suggestions would be helpful.ThanksKannan Always specify some constant value for timestamp. Only 1st insertion with that timestamp will succeed. Others will be ignored, because will be considered duplicates by cassandra.
RE: Preventing an update of a CF row
Reverse timestamp.
-Original Message-
From: Sylvain Lebresne [mailto:sylv...@yakaz.com]
Sent: Tuesday, October 19, 2010 10:44 AM
To: user@cassandra.apache.org
Subject: Re: Preventing an update of a CF row
Always specify some constant value for timestamp. Only 1st insertion with that
timestamp will succeed. Others will be ignored, because will be considered
duplicates by cassandra.
Well, that's not entirely true. When cassandra 'resolves' two columns
having the
same timestamp, it will compare the values to decide which one to keep
(and it'll
keep the one column whose value is greater for bytes comparison).
Concretely, if you insert Column('foo', 'b', 0) and then Column('foo',
'bar', 0), then
you'll end up with the second column, even though the timestamps are the same
because 'bar' 'b'.
So constant timestamps doesn't work for preventing updates of a given column.
--
Sylvain
RE: Booting Cassandra v0.7.0 on Windows: rename failed
This isn't a first time Cassandra has I/O issues on Windows. I think it's not easy to review source code and eliminate such issues, but would like developers to keep in mind such issues in the future. We're also running a Cassandra cluster on Windows, but 0.7 beta1 (with similar issue, but for Commit Log) and waiting for 0.7 release to use it fully on production. Viktor -Original Message- From: Jonathan Ellis [mailto:jbel...@gmail.com] Sent: Monday, November 29, 2010 5:09 PM To: user Subject: Re: Booting Cassandra v0.7.0 on Windows: rename failed Please report a bug at https://issues.apache.org/jira/browse/CASSANDRA On Mon, Nov 29, 2010 at 2:49 AM, Ramon Rockx r.ro...@asknow.nl wrote: Hi, Recently I downloaded Cassandra v0.7.0 rc1. When I try to run cassandra it ends with the following logging: INFO 09:17:30,044 Enqueuing flush of memtable-locationi...@839514767(643 bytes, 12 operations) INFO 09:17:30,045 Writing memtable-locationi...@839514767(643 bytes, 12 operations) ERROR 09:17:30,233 Fatal exception in thread Thread[FlushWriter:1,5,main] java.io.IOError: java.io.IOException: rename failed of d:\cassandra\data\system\LocationInfo-e-1-Data.db at org.apache.cassandra.io.sstable.SSTableWriter.rename(SSTableWriter.java: 214) at org.apache.cassandra.io.sstable.SSTableWriter.closeAndOpenReader(SSTable Writer.java:184) at org.apache.cassandra.io.sstable.SSTableWriter.closeAndOpenReader(SSTable Writer.java:167) at org.apache.cassandra.db.Memtable.writeSortedContents(Memtable.java:161) at org.apache.cassandra.db.Memtable.access$000(Memtable.java:49) at org.apache.cassandra.db.Memtable$1.runMayThrow(Memtable.java:174) at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:30) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) at java.util.concurrent.FutureTask.run(FutureTask.java:138) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecuto r.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.ja va:908) at java.lang.Thread.run(Thread.java:619) Caused by: java.io.IOException: rename failed of d:\cassandra\data\system\LocationInfo-e-1-Data.db at org.apache.cassandra.utils.FBUtilities.renameWithConfirm(FBUtilities.jav a:359) at org.apache.cassandra.io.sstable.SSTableWriter.rename(SSTableWriter.java: 210) ... 12 more Operating system is Windows 7. Tried it also on Windows 2003 server. I only modified a few (necessary) path settings in cassandra.yaml: commitlog_directory: d:/cassandra/commitlog data_file_directories: - d:/cassandra/data saved_caches_directory: d:/cassandra/saved_caches Does anybody know what I'm doing wrong? Regards, Ramon -- Jonathan Ellis Project Chair, Apache Cassandra co-founder of Riptano, the source for professional Cassandra support http://riptano.com
RE: Quorum: killing 1 out of 3 server kills the cluster (?)
With 3 nodes and RF=2 you have 3 key ranges: N1+N2, N2+N3 and N3+N1. Killing N1 you've got only 1 alive range N2+N3 and 2/3 of the range is down for Quorum, which is actually all, so N1+N2 and N3+N1 fails. -Original Message- From: Timo Nentwig [mailto:timo.nent...@toptarif.de] Sent: Thursday, December 09, 2010 6:01 PM To: user@cassandra.apache.org Subject: Re: Quorum: killing 1 out of 3 server kills the cluster (?) On Dec 9, 2010, at 16:50, Daniel Lundin wrote: Quorum is really only useful when RF 2, since the for a quorum to succeed RF/2+1 replicas must be available. 2/2+1==2 and I killed 1 of 3, so... don't get it. This means for RF = 2, consistency levels QUORUM and ALL yield the same result. /d On Thu, Dec 9, 2010 at 4:40 PM, Timo Nentwig timo.nent...@toptarif.de wrote: Hi! I've 3 servers running (0.7rc1) with a replication_factor of 2 and use quorum for writes. But when I shut down one of them UnavailableExceptions are thrown. Why is that? Isn't that the sense of quorum and a fault-tolerant DB that it continues with the remaining 2 nodes and redistributes the data to the broken one as soons as its up again? What may I be doing wrong? thx tcn
RE: [RELEASE] 0.7.0 (and 0.6.9)
Congratulations!!! Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 Konstitucijos pr. 23, LT-08105 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the interested recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete or destroy this message and any copies.-Original Message- From: Eric Evans [mailto:eev...@rackspace.com] Sent: Tuesday, January 11, 2011 19:23 To: user@cassandra.apache.org Subject: [RELEASE] 0.7.0 (and 0.6.9) As some of you may already be aware, 0.7.0 has been officially released. You are free to start your upgrades, though not all at once, you'll spoil your supper! I apologize to anyone that might have noticed artifacts published as early as Sunday and were confused by the lack of announcement, I was waiting for an Official ASF Press Release and my timing sucks. https://blogs.apache.org/foundation/entry/the_apache_software_foundation_announces9 There is way too much hotness in 0.7.0 to cover here, so instead I will refer you to the following articles. http://www.rackspacecloud.com/blog/2010/10/27/new-features-in-cassandra-0-7 http://www.riptano.com/blog/whats-new-cassandra-07-secondary-indexes http://www.riptano.com/blog/whats-new-cassandra-07-hadoop-output-cassandra http://www.riptano.com/blog/whats-new-cassandra-07-expiring-columns http://www.riptano.com/blog/whats-new-cassandra-07-live-schema-updates And of course, let's not forget the release notes. http://goo.gl/Bi8LD As usual you can download 0.7.0 from the website: http://cassandra.apache.org/download Users of Debian and derivatives can install from our repository: http://wiki.apache.org/cassandra/DebianPackaging New for 0.7.0, Cassandra is also available from Maven Central (thanks Stephen Connolly). But wait, there's more! If you're not in a hurry to upgrade, we have a new 0.6 release as well, 0.6.9. It's an easy upgrade for anyone running 0.6.8 and contains a number of useful changes (http://goo.gl/6NIPG). The Debian repository has been extended to support an extra version so if you're accustomed to installing 0.6 from our repository, then be sure to change your suite name to 06x in sources.list. For example: deb http://www.apache.org/dist/cassandra/debian 06x main deb-src http://www.apache.org/dist/cassandra/debian 06x main That's it, thanks everyone! -- Eric Evans eev...@rackspace.com
RE: about the data directory
I have 4 nodes, then I I create one keyspace (such as FOO) with replica factor =1 and insert an data, why I can see the directory of /var/lib/Cassandra/data/FOO in every nodes? As I know, I just have one replica So why do you have installed 4 nodes, not 1? They're for your data to be distributed between 4 nodes with 1 copy on one of them. This is like you have 100% of data and each node will have 25% of the data (random partitioning). Viktor. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 Konstitucijos pr. 23, LT-08105 Vilnius, Lithuania [cid:signature-logo6784.png]http://www.adform.com/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the interested recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete or destroy this message and any copies. inline: signature-logo6784.png
RE: Do you have a site in production environment with Cassandra? What client do you use?
- Cassandra 0.7 beta1 on virtual Windows Server 2008 64bit machines (8 total). - In-house built C# client for .NET app connecting using Thrift, was worth it to built own client. - 150M transactions/day load and growing. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 Konstitucijos pr. 23, LT-08105 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the interested recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete or destroy this message and any copies.-Original Message- From: Ertio Lew [mailto:ertio...@gmail.com] Sent: Friday, January 14, 2011 19:25 To: user Subject: Do you have a site in production environment with Cassandra? What client do you use? Hey, If you have a site in production environment or considering so, what is the client that you use to interact with Cassandra. I know that there are several clients available out there according to the language you use but I would love to know what clients are being used widely in production environments and are best to work with(support most required features for performance). Also preferably tell about the technology stack for your applications. Any suggestions, comments appreciated ? Thanks Ertio
RE: Do supercolumns have a purpose?
SCFs are very useful and I hope lives forever. We need them! Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 Konstitucijos pr. 23, LT-08105 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the interested recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete or destroy this message and any copies.-Original Message- From: norman.mau...@googlemail.com [mailto:norman.mau...@googlemail.com] On Behalf Of Norman Maurer Sent: Wednesday, February 09, 2011 20:59 To: user@cassandra.apache.org Subject: Re: Do supercolumns have a purpose? I still think super-columns are useful you just need to be aware of the limitations... Bye, Norman 2011/2/9 Mike Malone m...@simplegeo.com: On Tue, Feb 8, 2011 at 2:03 AM, David Boxenhorn da...@lookin2.com wrote: Shaun, I agree with you, but marking them as deprecated is not good enough for me. I can't easily stop using supercolumns. I need an upgrade path. David, Cassandra is open source and community developed. The right thing to do is what's best for the community, which sometimes conflicts with what's best for individual users. Such strife should be minimized, it will never be eliminated. Luckily, because this is an open source, liberal licensed project, if you feel strongly about something you should feel free to add whatever features you want yourself. I'm sure other people in your situation will thank you for it. At a minimum I think it would behoove you to re-read some of the comments here re: why super columns aren't really needed and take another look at your data model and code. I would actually be quite surprised to find a use of super columns that could not be trivially converted to normal columns. In fact, it should be possible to do at the framework/client library layer - you probably wouldn't even need to change any application code. Mike On Tue, Feb 8, 2011 at 3:53 AM, Shaun Cutts sh...@cuttshome.net wrote: I'm a newbie here, but, with apologies for my presumptuousness, I think you should deprecate SuperColumns. They are already distracting you, and as the years go by the cost of supporting them as you add more and more functionality is only likely to get worse. It would be better to concentrate on making the core column families better (and I'm sure we can all think of lots of things we'd like). Just dropping SuperColumns would be bad for your reputation -- and for users like David who are currently using them. But if you mark them clearly as deprecated and explain why and what to do instead (perhaps putting a bit of effort into migration tools... or even a virtual layer supporting arbitrary hierarchical data), then you can drop them in a few years (when you get to 1.0, say), without people feeling betrayed. -- Shaun On Feb 6, 2011, at 3:48 AM, David Boxenhorn wrote: My main point was to say that it's think it is better to create tickets for what you want, rather than for something else completely different that would, as a by-product, give you what you want. Then let me say what I want: I want supercolumn families to have any feature that regular column families have. My data model is full of supercolumns. I used them, even though I knew it didn't *have to*, because they were there, which implied to me that I was supposed to use them for some good reason. Now I suspect that they will gradually become less and less functional, as features are added to regular column families and not supported for supercolumn families. On Fri, Feb 4, 2011 at 10:58 AM, Sylvain Lebresne sylv...@datastax.com wrote: On Fri, Feb 4, 2011 at 12:35 AM, Mike Malone m...@simplegeo.com wrote: On Thu, Feb 3, 2011 at 6:44 AM, Sylvain Lebresne sylv...@datastax.com wrote: On Thu, Feb 3, 2011 at 3:00 PM, David Boxenhorn da...@lookin2.com wrote: The advantage would be to enable secondary indexes on supercolumn families. Then I suggest opening a ticket for adding secondary indexes to supercolumn families and voting on it. This will be 1 or 2 order of magnitude less work than getting rid of super column internally, and probably a much better solution anyway. I realize that this is largely subjective, and on such matters code speaks louder than words, but I don't think I agree with you on the issue of which alternative is less work, or even which is a better solution. You are right, I put probably too much emphase in that sentence. My main point was to say that it's think it is better to create tickets for what you want, rather than for something else
Reads and memory usage clarification
Hello, Write path is perfectly documented in architecture overview. I need Reads to be clarified: How memory is used 1. When data is in the Memtable 2. When data is in the SSTable How cache is used alongside with Memtable? Are records created in the Memtable from writes only or from reads also? What I need to know is, how Cassandra uses memory and Memtables for reads? Thenk you, Viktor
Re: Reads and memory usage clarification
Everything as I thought, thank you! 2011/2/23 Matthew Dennis mden...@datastax.com Data is in Memtables from writes before they get flushed (based on first threshold of ops/size/time exceeded; all are configurable) to SSTables on disk. There is a keycache and a rowcache. The keycache caches offsets into SSTables for the rows. the rowcache caches the entire row. There is also the OS page cache which is heavily used. When a read happens, the keycache is updated with the information for the SSTables the row was eventually found in. If there are too many entries now in the keycache, some are ejected. Overall the keycache uses very little memory per entry and can cut your disk IO in half so it's a pretty big win. If you read an entire row it goes in the row cache. Like the keycache, this may result in older entries being ejected from the cache. If you insert lots of really large rows in the rowcache you can OOM your JVM. The rowcache is kept up to date with the memtables as writes come in. When a read comes in, C* will collect the data from the SSTables and Memtables and merge them together but data only goes into Memtables from writes. On Tue, Feb 22, 2011 at 3:32 AM, Viktor Jevdokimov vjevdoki...@gmail.comwrote: Hello, Write path is perfectly documented in architecture overview. I need Reads to be clarified: How memory is used 1. When data is in the Memtable 2. When data is in the SSTable How cache is used alongside with Memtable? Are records created in the Memtable from writes only or from reads also? What I need to know is, how Cassandra uses memory and Memtables for reads? Thenk you, Viktor
Cassandra on Windows network latency
Hi all, We have installed Cassandra on Windows and found that with any number of Cassandra (single, or 3 node cluster) on Windows Vista or Windows Server 2008, 32 or 64 bit, with any load or number of requests we, have: When client and server are on the same machine, connect/read/write latencies ~0-1ms When client on another machine, same network, on the same switch, connection latency 0-1ms (as a ping), read/write latencies =200ms. What causes 200ms latency accessing Cassandra on Windows through network? Does anybody experience such behavior? Cassandra 0.6.1 Java SE 6 u20 Best regards, Viktor
