Re: Service discovery in the Cassandra cluster

gt; >> On May 1, 2017, at 3:50 PM, Jon Haddad wrote: >> >> Sure, you could use DNS. Where does it say IP addresses are a >> requirement? >> >> On May 1, 2017, at 1:36 PM, Roman Naumenko wrote: >> >> If I understand how Cassandra nodes work, they must contain a list of >> seed’s IP addressed in

Re: results differ on two queries, based on secondary index key and partition key

; to our clients any opinions or advice contained in this Email are subject > to the terms and conditions expressed in any applicable governing The Home > Depot terms of business or client engagement letter. The Home Depot > disclaims all responsibility and liability for the accuracy and co

Re: Unable to perform COUNT(*) on CASSANDRA table

'cold_reads_to_omit' : 0.05, > > 'enabled' : true, > > 'max_threshold' : 32, > > 'min_sstable_size' : 50, > > 'min_threshold' : 4, > > 'tombsto

Re: Is it possible to achieve "sticky" request routing?

you're trying to do a coordinator tier (and you're not, according >> to your original post), this is a pretty bad idea and I'd advise you to >> push back on that requirement. >> >> On Tue, Apr 5, 2016 at 12:47 PM Steve Robenalt >> wrote: >> >

Re: Is it possible to achieve "sticky" request routing?

gt; >> 2. Write a new load balancing policy that also uses the HostStateListener >> for tracking host up and down messages, that essentially accomplishes >> "sticky" request routing with failover to other nodes. >> >> Is option 2 the only clean way of accomplish

Re: Large number of tombstones without delete or update

; wrote: >> >>> On Wed, Mar 23, 2016 at 9:50 AM, Ralf Steppacher >> > wrote: >>> >>>> How come I end up with that large a number of tombstones? >>>> >>> >>> Are you inserting NULLs? >>> >>> =Rob >>>

Re: Experiencing strange disconnect issue

r the addressee. Access to this Email >> by anyone else is unauthorized. If you are not the intended recipient, any >> disclosure, copying, distribution or any action taken or omitted to be >> taken in reliance on it, is prohibited and may be unlawful. When addressed >> to

Re: Experiencing strange disconnect issue

It all goes south at about line 433 (time 19:46:43) where the client > throws a: > io.netty.handler.codec.DecoderException: > com.datastax.driver.core.exceptions.DriverInternalError: Adjusted frame > length exceeds 268435456: 462591744 - discarded > > Any ideas? > > ons.

Re: nulls in prepared statement & tombstones?

.2.0): > https://issues.apache.org/jira/browse/CASSANDRA-7304 > > Adam > > On Tue, Mar 8, 2016 at 12:15 PM, Henry M wrote: > >> Thank you. It's probably not specific to prepared statements then and >> just a more general statement. That makes sense. >> >>

Re: nulls in prepared statement & tombstones?

one could help explain why sending nulls as part of > a prepared statement update would result in tombstones. > > Thank you, > - Henry > -- Steve Robenalt Software Architect sroben...@highwire.org (office/cell): 916-505-1785 HighWire Press, Inc. 425 Broadway St, Redwood City, CA 94063 www.highwire.org Technology for Scholarly Communication

Re: EC2 storage options for C*

Instances" should be publicly recommended going forward. > > And whether non-SSD instances should be recommended going forward as well. > sure, technically, someone could use the legacy instances, but the question > is what we should be recommending as best practice going forward. > >

Re: EC2 storage options for C*

well. > sure, technically, someone could use the legacy instances, but the question > is what we should be recommending as best practice going forward. > > Yeah, the i2 instances look like the sweet spot for any non-EBS clusters. > > -- Jack Krupansky > > On Mon, Feb 1, 20

Re: EC2 storage options for C*

ly use PIOPS or just standard GP2 in your production >>>>>> cluster? >>>>>> >>>>>> On Sat, Jan 30, 2016 at 1:28 PM, Bryan Cheng >>>>>> wrote: >>>>>> >>>>>>> Yep, that motivated my question "Do you have any idea what kind of >>>>>>> disk performance you need?". If you need the performance, its hard to >>>>>>> beat >>>>>>> ephemeral SSD in RAID 0 on EC2, and its a solid, battle tested >>>>>>> configuration. If you don't, though, EBS GP2 will save a _lot_ of >>>>>>> headache. >>>>>>> >>>>>>> Personally, on small clusters like ours (12 nodes), we've found our >>>>>>> choice of instance dictated much more by the balance of price, CPU, and >>>>>>> memory. We're using GP2 SSD and we find that for our patterns the disk >>>>>>> is >>>>>>> rarely the bottleneck. YMMV, of course. >>>>>>> >>>>>>> On Fri, Jan 29, 2016 at 7:32 PM, Jeff Jirsa < >>>>>>> jeff.ji...@crowdstrike.com> wrote: >>>>>>> >>>>>>>> If you have to ask that question, I strongly recommend m4 or c4 >>>>>>>> instances with GP2 EBS. When you don’t care about replacing a node >>>>>>>> because >>>>>>>> of an instance failure, go with i2+ephemerals. Until then, GP2 EBS is >>>>>>>> capable of amazing things, and greatly simplifies life. >>>>>>>> >>>>>>>> We gave a talk on this topic at both Cassandra Summit and AWS >>>>>>>> re:Invent: https://www.youtube.com/watch?v=1R-mgOcOSd4 It’s very >>>>>>>> much a viable option, despite any old documents online that say >>>>>>>> otherwise. >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> From: Eric Plowe >>>>>>>> Reply-To: "user@cassandra.apache.org" >>>>>>>> Date: Friday, January 29, 2016 at 4:33 PM >>>>>>>> To: "user@cassandra.apache.org" >>>>>>>> Subject: EC2 storage options for C* >>>>>>>> >>>>>>>> My company is planning on rolling out a C* cluster in EC2. We are >>>>>>>> thinking about going with ephemeral SSDs. The question is this: Should >>>>>>>> we >>>>>>>> put two in RAID 0 or just go with one? We currently run a cluster in >>>>>>>> our >>>>>>>> data center with 2 250gig Samsung 850 EVO's in RAID 0 and we are happy >>>>>>>> with >>>>>>>> the performance we are seeing thus far. >>>>>>>> >>>>>>>> Thanks! >>>>>>>> >>>>>>>> Eric >>>>>>>> >>>>>>> >>>>>>> >>>>>> >>>>> >> > -- Steve Robenalt Software Architect sroben...@highwire.org (office/cell): 916-505-1785 HighWire Press, Inc. 425 Broadway St, Redwood City, CA 94063 www.highwire.org Technology for Scholarly Communication

Re: Cassandra driver class

gt; Is “com.datastax.driver.core” even correct, or am I going down the >>>> wrong path? I am using the DataStax 2.0.2 driver, with Cassandra 2.0.8. >>>> >>>> >>>> >>>> Should I be using instead of ? >>>> >>>> >>>> >>>> Does anybody have a working example they can share? Any help to get me >>>> going would be appreciated. Thanks. >>>> >>>> >>>> >>>> Bill >>>> >>>> >>>> >>>> >>>> >>> >>> >>> >>> -- >>> Bests, >>> >>> Alex Popescu | @al3xandru >>> Sen. Product Manager @ DataStax >>> >>> >> >> -- >> -- >> Bestdata.be >> Optimised ict >> Tel:+32(0)496609576 >> co...@bestdata.be >> -- >> >> > -- Steve Robenalt Software Architect sroben...@highwire.org (office/cell): 916-505-1785 HighWire Press, Inc. 425 Broadway St, Redwood City, CA 94063 www.highwire.org Technology for Scholarly Communication

Re: Questions about the replicas selection and remote coordinator

here, > https://docs.datastax.com/en/cassandra/2.1/cassandra/dml/architectureClientRequestsMultiDCWrites_c.html. > It > shows that node 10 in DC 1 will send directly 3 copies to 3 nodes in DC2, > without using remote coordinator. > > I'm wondering which case is true, becau

Re: Questions about the replicas selection and remote coordinator

e two methods varies a lot. > > Also, is there any mechanism to select which node to be remote > coordinator? > > Thanks! > > Jun > -- Steve Robenalt Software Architect sroben...@highwire.org (office/cell): 916-505-1785 HighWire Press, Inc. 425 Broadway St, Redwood City, CA 94063 www.highwire.org Technology for Scholarly Communication

Re: Using cassandra a BLOB store / web cache.

a blob, >> PRIMARY KEY (file_id, num) >> ); >> >> For your purposes you could modify the objects table to keep a revision >> id or timeuuid for looking at previous versions. If you want some insight >> into how the code worked give me a shout. >> > > > > -- > -Richard L. Burton III > @rburton > -- Steve Robenalt Software Architect sroben...@highwire.org (office/cell): 916-505-1785 HighWire Press, Inc. 425 Broadway St, Redwood City, CA 94063 www.highwire.org Technology for Scholarly Communication

Re: Query Consistency Issues...

hey need to be? >>> >>> >>>> If you have high frequency updates in the same partition from the same >>>> client you should probably use client-side timestamps with a configured >>>> timestamp generator on the driver, available in Cassandra 2.1 and Java >>>> driver 2.1.2, and default in java driver 3.0. >>>> >>>> >>> Very cool! If we have multiple nodes in our application, I suppose >>> *their* clocks will have to be sync'ed for this to work, right? >>> >> >> -- Steve Robenalt Software Architect sroben...@highwire.org (office/cell): 916-505-1785 HighWire Press, Inc. 425 Broadway St, Redwood City, CA 94063 www.highwire.org Technology for Scholarly Communication

Re: Cassandra and GPU's...

potential impact on the Spark and/or Titan integration with Cassandra, rather than on Cassandra itself. Steve On Tue, Dec 1, 2015 at 12:35 PM, james anderson wrote: > good evening; > > On 2015-12-01, at 21:17, Steve Robenalt wrote: > > Hi Tony, > > Somebody will likely prove me w

Re: Cassandra and GPU's...

; Can Cassandra use GPU's? If not can someone recommend a open source > database that runs on GPU's? I am interested in seeing the performance > difference of a database that is under 2GB run on a GPU card such as as > NVIDA gtx 980. > > Thanks, > -Tony > -- Steve

Re: unsubscribe

:44 AM, Brian Tarbox wrote: > unsubscribe > > -- > http://about.me/BrianTarbox > -- Steve Robenalt Software Architect sroben...@highwire.org (office/cell): 916-505-1785 HighWire Press, Inc. 425 Broadway St, Redwood City, CA 94063 www.highwire.org Technology for Scholarly Communication

Re: Is replication possible with already existing data?

t; >> >> What changes need to be made, so that whenever a downed server comes back >> up, the missing data comes back over to it? >> >> Thanks and Regards, >> Ajay >> >> >> >> On Fri, Oct 23, 2015 at 9:05 AM, Michael Shuler >>

Re: Realtime data and (C)AP

y fall back to local_one in the cases where some data fast is > better than a failure. Currently we do that on a per read basis but we > could I suppose detect a pattern or just look at the gossip to decide to go > en masse into a degraded read mode > > Sent from my iPhone > > On O

Re: Realtime data and (C)AP

endent on the nature of the workload. Steve On Fri, Oct 9, 2015 at 12:36 PM, Brice Dutheil wrote: > On Fri, Oct 9, 2015 at 2:27 AM, Steve Robenalt > wrote: > > In general, if you write at QUORUM and read at ONE (or LOCAL variants >> thereof if you have multiple data centers

Re: Realtime data and (C)AP

of the CAP theorem. So how Cassandra can >> deliver realtime consistent data? >> AFAIK, choosing a consistency level equals to ALL can be a huge >> performance hit for C*, so, please, explain me why I should choose C* >> for realtime data >> that should be consistent acr

Re: INSERT JSON TimeStamp

"action": "FareAmount=9.25", > "ruleOrder": "1" > } > } > > message="Error decoding JSON value for effectivestartdate: Unable to > coerce '01/01/2015' to a formatted date (long)" > -- Steve Robenalt Software Architect sroben...@highwire.org (office/cell): 916-505-1785 HighWire Press, Inc. 425 Broadway St, Redwood City, CA 94063 www.highwire.org Technology for Scholarly Communication

Re: Cassandra Summit 2015 Roll Call!

nd connect > with other attendees! > > > > MY CONTRIBUTION : > > -- > > I will be at the summit on Wednesday and Thursday. I am 5'8" or so, and > will be wearing glasses and either a red or blue "Eventbrite Engineering" > t-shirt with a graphic logo of gears on it. Come say hello! :D > > > > =Rob > > > > > -- Steve Robenalt Software Architect sroben...@highwire.org (office/cell): 916-505-1785 HighWire Press, Inc. 425 Broadway St, Redwood City, CA 94063 www.highwire.org Technology for Scholarly Communication

Re: Denormalization leads to terrible, rather than better, Cassandra performance -- I am really puzzled

A few observations from what you've said so far: 1) IN clauses in CQL can have performance impact by including sets of keys that are spread across the cluster. 2) We previously used m3.large instances in our cluster and would see occasional read timeouts even at CL.ONE. We upgraded to i2.xlarge w

Re: Fwd: ReadTimeoutException in Cassandra 2.0.11

on the Server and trying to process 200B. ( 1GB is > allocated to Tomcat7, 1 GB to Cassandra and 1 GB to ActiveMQ. Also nltk > Server is running) > 3. We are using 2.03 Driver (This is one I can change and try) > 4. 64.4 GB HDD > 5. Attached Memory and CPU information. > > Regards

Re: Fwd: ReadTimeoutException in Cassandra 2.0.11

I agree with Rob. You shouldn't need to change the read timeout. We had similar issues with intermittent ReadTimeoutExceptions for a while when we ran Cassandra on underpowered nodes on AWS. We've also seen them when executing unconstrained queries with very large ResultSets (because it takes long

Re: Question about EC2 and SSDs

, "Robert Coli" wrote: > On Thu, Sep 4, 2014 at 5:44 PM, Steve Robenalt > wrote: > >> Thanks Robert! I am assuming that you meant that it's possible with a >> single SSD, right? >> > > Yes, no matter how many SSDs you have you are unlikely to be abl

Re: Question about EC2 and SSDs

Thanks Robert! I am assuming that you meant that it's possible with a single SSD, right? On Thu, Sep 4, 2014 at 5:42 PM, Robert Coli wrote: > On Thu, Sep 4, 2014 at 5:05 PM, Steve Robenalt > wrote: > >> We are migrating a small cluster on AWS from instances based on spin

Re: Question about EC2 and SSDs

antan > > > On Sep 4, 2014, at 8:05 PM, Steve Robenalt > wrote: > > > > Hi all, > > > > We are migrating a small cluster on AWS from instances based on spinning > disks (using instance store) to SSD-backed instances and we're trying to > pick the p

Question about EC2 and SSDs

Hi all, We are migrating a small cluster on AWS from instances based on spinning disks (using instance store) to SSD-backed instances and we're trying to pick the proper instance type. Some of the recommendations for spinning disks say to use different drives for log vs data partitions to avoid is