Aaron first of all thanks for your great support.
I'm paranoid, so I would upgrade 1 node and let it soak in for a few
hours. Nothing like upgrading an entire cluster and then discovering a
problem.
Ok but as far as my application is concerned is safe to keep a cluster with
part o
> I use a batch mutator in Pycassa to delete ~1M rows based on
> a longish list of keys I'm extracting from an auxiliary CF (with no
> problem of any sort).
What is the size of the deletion batches ?
> Now, it appears that such heads-on delete puts a temporary
> but large load on the cluster. I ha
Hi there,
I'm running a cassandra 0.8.6 cluster with 2 nodes (in 2 DC's), RF = 2.
Actual data on the nodes is only 1GB. Disk latency < 1ms. Disk throughput ~
0.4MB/s. OS load always below 1 (on a 8 core machine with 16GB ram).
When I'm running my writes against the cluster with cl = ONE all reads
What can you see in vmstat/dstat ?
Le 5 janv. 2012 11:58, "R. Verlangen" a écrit :
> Hi there,
>
> I'm running a cassandra 0.8.6 cluster with 2 nodes (in 2 DC's), RF = 2.
> Actual data on the nodes is only 1GB. Disk latency < 1ms. Disk throughput ~
> 0.4MB/s. OS load always below 1 (on a 8 core m
CPU is idle (< 10% usage). Disk reads occasionally blocks over 32/64K.
Writes around 0-5MB per second. Network traffic 0.1 / 0.1 MB/s (in / out).
Paging 0. System int ~ 1300, csw ~ 2500.
2012/1/5 Philippe
> What can you see in vmstat/dstat ?
> Le 5 janv. 2012 11:58, "R. Verlangen" a écrit :
>
>
As I posted this I noticed that the other node's CPU is running high on
some other cronjobs (every couple of minutes to 60% usage). Is the lack of
more CPU cycles a problem in this case?
Robin
2012/1/5 R. Verlangen
> CPU is idle (< 10% usage). Disk reads occasionally blocks over 32/64K.
> Write
I missed a ! in the code :) The query will break the token ring into ranges
based on the node tokens and then find the UP nodes for each range.
I've taken another walk through the code, the logs helped.
In short, you do not have enough UP nodes to support an indexed get at CL ONE.
It is worki
Sort of. Depends.
In Cassandra automatic memory management means the server can support more CF's
and it has apparently been tested to 100's or 1000's of CF's. Having lots of
CF's will impact performance by putting memory and IO under pressure though.
If you have 10's you should not have to w
> Ok but as far as my application is concerned is safe to keep a cluster with
> part of 1.0 and part of 0.7?
I *think* it should be so long as it's a short time and you do not run any
repairs.
If 1.0 creates any new files, via mutations or compaction, they will not be
readable by 0.7. So the r
Hi,
On Wed, Jan 4, 2012 at 9:54 PM, aaron morton wrote:
> Some thoughts on the plan:
>
> * You are monkeying around with things, do not be surprised when
> surprising things happen.
>
I am just trying to explore different solutions for solving my problem.
> * Deliberately unbalancing the clust
Is there a doc for using composite columns with thrift?
Is
https://github.com/apache/cassandra/blob/trunk/src/java/org/apache/cassandra/db/marshal/CompositeType.java
the
only doc?
does the client needs to add the length to the get \ get_slice... queries
or is it taken care of on the server side?
S
My 0.8 production cluster contains around 150 CFs spread across 5
keyspaces. Haven't found that to be an issue (yet?).
Some of them are huge (dozens of GB), some are tiny (some MB).
Cheers
2012/1/5 aaron morton
> Sort of. Depends.
>
> In Cassandra automatic memory management means the server ca
Depending on the CL you're reading at it will yes : if the CL requires that
the "slow" node create a digest of the data and send it to the coordinator
then it might explain the poor performance on reads. What is your read CL ?
2012/1/5 R. Verlangen
> As I posted this I noticed that the other nod
I'm also reading with CL = ONE
2012/1/5 Philippe
> Depending on the CL you're reading at it will yes : if the CL requires
> that the "slow" node create a digest of the data and send it to the
> coordinator then it might explain the poor performance on reads. What is
> your read CL ?
>
> 2012/1/5
What if you shutdown the cassandra service on the slow node, does that
improve your read performance ?
If it does then that sole node is responsible for the slow down because it
can't act as a coordinator fast enough.
2012/1/5 R. Verlangen
> I'm also reading with CL = ONE
>
>
> 2012/1/5 Philippe
It does not appear to affect the response time, certainly not in a positive
way.
2012/1/5 Philippe
> What if you shutdown the cassandra service on the slow node, does that
> improve your read performance ?
> If it does then that sole node is responsible for the slow down because it
> can't act a
You may be overloading the cluster though...
My hypothesis is that your traffic is being spread across your node and
that one slow node is slowing down the fraction of traffic that goes to
that node (when it's acting as coordinator).
So what I would do is reduce the read load a lot to make sure I
Good afternoon,
I am curious if anyone here has taken the libQtCassandra high-level client and
stripped-out the Qt pieces to make it Qt independent?
Thanks,
David Gosselin
Senior Software Engineer
Acme Packet
(781) 328-2604
The write and read load is very minimal the moment. Roughly 10 writes + 10
reads / second. So 20 operations per second. Don't think that overloads my
cluster, does it?
2012/1/5 Philippe
> You may be overloading the cluster though...
>
> My hypothesis is that your traffic is being spread across y
Hi Folk,
I am a beginner user in Cassandra. I have a question about the usage and
integration (or installation) hector into eclipse IDE? I try to find the
answer
by googling, but I do not find a proper guidance to do it. Would you want
to help me
by telling me how to do it or showing me the proper
2012/1/5 Michael Cetrulo
> in a traditional database it's not a good a idea to have hundreds of
> tables but is it also bad to have hundreds of column families in cassandra?
> thank you.
>
As far as I can see, this may raise memory requirements for you, since you
need to have index/bloom filter
Hi There,
I am a beginner user in Cassandra. I hear from many people said Cassandra is
a powerful database software which is used by Facebook, Twitter, Digg, etc.
So I feel interesting to study more about Cassandra.
When I performed integration process between Cassandra with Eclipse IDE (in
this
Thanks Aaron.
Michael
From: aaron morton [mailto:aa...@thelastpickle.com]
Sent: Wednesday, January 04, 2012 10:06 PM
To: user@cassandra.apache.org
Subject: Re: java.lang.AssertionError
Will be fixed in 1.0.7 https://issues.apache.org/jira/browse/CASSANDRA-3656
Cheers
-
Unless you are doing huge batches no... don't have any other idea for now...
2012/1/5 R. Verlangen
> The write and read load is very minimal the moment. Roughly 10 writes + 10
> reads / second. So 20 operations per second. Don't think that overloads my
> cluster, does it?
>
>
> 2012/1/5 Philippe
Hello,
We are working on some new cassandra requirements and I wanted to get your
recommendations on how to go ahead and put schema in place in terms of how
many CF one should have for below scenario:
1- There are 10 applications. Out of which 1 or 2 applications are very
active giving 90%+ load.
Hector is a library. It needs to be added to your Eclipse project's "build
classpath"
somehow before you can begin using it in Eclipse.
On Thu, Jan 05, 2012 at 11:25:16PM +0700, dir dir wrote:
>Hi Folk,
>I am a beginner user in Cassandra. I have a question about the usage and
>integra
> * In the design discussed it is perfectly reasonable for data not to be on
> the archive node.
>
> You mean when having the 2 DC setup I mentioned and using TTL? In case I have
> the 2 DC setup but don't use TTL I don't understand why data wouldn't be on
> the archive node?
Originally you we
What client are you using ?
For example pycassa has some sweet documentation
http://pycassa.github.com/pycassa/assorted/composite_types.html
Cheers
-
Aaron Morton
Freelance Developer
@aaronmorton
http://www.thelastpickle.com
On 6/01/2012, at 12:48 AM, Shimi Kiviti wrote:
> Is
What happens when you turn off the cron jobs ?
Cheers
-
Aaron Morton
Freelance Developer
@aaronmorton
http://www.thelastpickle.com
On 6/01/2012, at 6:57 AM, Philippe wrote:
> Unless you are doing huge batches no... don't have any other idea for now...
>
> 2012/1/5 R. Verlangen
Hello Aaron,
On 1/5/2012 4:25 AM, aaron morton wrote:
I use a batch mutator in Pycassa to delete ~1M rows based on
a longish list of keys I'm extracting from an auxiliary CF (with no
problem of any sort).
What is the size of the deletion batches ?
2000 mutations.
Now, it appears that suc
I turned off 1 large cronjob which caused the CPU not to get used for ~ 60%
once every 10 minutes. Both write and read are fast now. Just think I was
overloading the node.
Weird though that shutting down the node did not improve the speed.
Thank you all for your time!
Robin
2012/1/5 aaron morto
I hate to admit it, but I use maven to get the classpaths right in Eclipse:
org.apache.cassandra
cassandra-all
1.0.6
jar
compile
org.cassandraunit
cassandra
If you are looking to add hector, you'll need:
me.prettyprint hector
1.0-2
-brian
Brian O'Neill
Lead Architect, Software Development
Health Market Science | 2700 Horizon Drive | King of Prussia, PA 19406
p: 215.588.6024blog: http://weblogs.java.net/blog/boneill42/
blog: http://bria
>
> Then I do have a question, what do people generally use as the batch size?
>
I used to do batches from 500 to 2000 like you do.
After investigating issues such as the one you've encountered I've moved to
batches of 20 for writes and 256 for reads. Everything is a lot smoother :
no more timeouts
Does index for CFs must fit in node's memory?
2012/1/5 Віталій Тимчишин
>
>
> 2012/1/5 Michael Cetrulo
>
>> in a traditional database it's not a good a idea to have hundreds of
>> tables but is it also bad to have hundreds of column families in cassandra?
>> thank you.
>>
>
> As far as I can se
Thanks, that's quite helpful. I'm wondering though if multiplying the
number of clients will
end up doing same thing.
On 1/5/2012 3:29 PM, Philippe wrote:
Then I do have a question, what do people generally use as the
batch size?
I used to do batches from 500 to 2000 like you do.
Afte
I wouldn't worry about the warnings. Eclipse Java support defaults to fairly
restrictive warning settings. You can go into the preferences for
Java->Compiler and change the 'warning' settings to 'ignore' for any of those
problems that you don't or shouldn't really care about.
As for the error
How about to use "File->Import..." rather than "File->New Java Project"?
After extracting the source, ant build, and ant generate-eclipse-files:
1. File->Import...
2. Choose "Existing Project into workspace..."
3. Choose your source directory as root directory and then push "Finish"
2012/1/6 bob
Sorry, ignore my reply.
I had same result with import. ( 1 error in unit test code & many warnings )
2012/1/6 Maki Watanabe :
> How about to use "File->Import..." rather than "File->New Java Project"?
>
> After extracting the source, ant build, and ant generate-eclipse-files:
> 1. File->Import...
Also note that Cassandra project switched to git from svn.
See "Source control" section of http://cassandra.apache.org/download/ .
Regards,
Yuki
--
Yuki Morishita
On Thursday, January 5, 2012 at 7:59 PM, Maki Watanabe wrote:
> Sorry, ignore my reply.
> I had same result with import. ( 1 err
Hi,
Can you post the error(saying that only 1 error is there), that'll make things
more clear.
Thanks
Kuldeep Singh Sengar
Opera Solutions
Tech Boulevard,8th floor, Tower C,
Sector 127, Plot No 6,Noida 201 301
+91 (120) 4642424 facsimile, Ext : 2418
+91 8800595878 (M)
-Original Message---
This works for me
http://wiki.apache.org/cassandra/HowToDebug
On 01/06/2012 01:18 AM, Kuldeep Sengar wrote:
Hi,
Can you post the error(saying that only 1 error is there), that'll make things
more clear.
Thanks
Kuldeep Singh Sengar
Opera Solutions
Tech Boulevard,8th floor, Tower C,
Sector 1
Thanks Aaron, I was able to complete the repair by scrubbing the column
family on all three replicas.
Cheers
2012/1/4 aaron morton
> I was able to scrub the node the repair that failed was running on. Are
> you saying the error could be displayed on that node but the bad data
> coming from anot
43 matches
Mail list logo
