Re: Anti-compaction Diskspace issue even when latest patch applied
Thanks for the pointer. Wanted to figure out if this is the real bottleneck as there might be something else contributing to the low speed. Let me explain our setup in more detail: We are using cassandra to store about 700 million images. This includes image metadata and the image (in binary format). In the data folder, I see about 53,831 files in the data folder. There are also about 3,940 files which have names like imagestore-b-66171-Data.db imagestore-b-66171-Filter.db I assume the latter are the compacted files. This set of files is indeed growing. The problem is that one node is our cluster is 4.5TB full and we are trying to load balance away from that node. I moved this node to a larger hard disk and trying out the load balance, but it is really slow. When I do the load balancing, row mutations are taking place and compaction is still continuing. The load balancing is happening at the rate of 10 MB per half hour. I suspect this is due to the compaction (and the anti-compaction). Now for questions: 1. Is there a way to estimate the time it would take to compact this work load? I hope the load balancing will be much faster after the compaction. Curious how fast I can get the transfer once compaction is done. 2. Any way to make this faster? Is working on the above issue the lowest hanging fruit or is there something else? Thanks, Shiv From: Jonathan Ellis jbel...@gmail.com To: cassandra-user@incubator.apache.org Sent: Thu, March 4, 2010 8:31:16 AM Subject: Re: Anti-compaction Diskspace issue even when latest patch applied https://issues.apache.org/jira/browse/CASSANDRA-579 should make a big difference in speed. If you want to take a stab at it I can point you in the right direction. :) On Thu, Mar 4, 2010 at 10:24 AM, shiv shivaji shivaji...@yahoo.com wrote: Yes. The IP change trick seems to work. Load balancing seems a little slow, but I will open a new thread on that if needed. Thanks, Shiv From: Jonathan Ellis jbel...@gmail.com To: cassandra-user@incubator.apache.org Sent: Wed, March 3, 2010 9:21:28 AM Subject: Re: Anti-compaction Diskspace issue even when latest patch applied You are proposing manually moving your data from a 5TB disk to a 12TB disk, and that is the only change you want to make? Then just keep the IP the same when you restart it after moving, and you won't have to do anything else, it will just look like the node was down temporarily and is now back up. On Tue, Mar 2, 2010 at 7:26 PM, shiv shivaji shivaji...@yahoo.com wrote: Thanks, just realized this after looking at the source code. Seems like the decommission will not work for me due to disk space issues. I am currently moving all the data on the heavy node (5 TB full) to a 12 TB disk drive. I am planning to remove the old token and resign the old token to this node. According to the docs, it says to use decommission, however lack of disk space does not allow me to do this. If I manually move all the data files and then do a removetoken and start the node with a new token, would that work (as was implied in a JIRA)? Shiv From: Stu Hood stu.h...@rackspace.com To: cassandra-user@incubator.apache.org Sent: Sun, February 28, 2010 1:53:29 PM Subject: Re: Anti-compaction Diskspace issue even when latest patch applied `nodetool cleanup` is a very expensive process: it performs a major compaction, and should not be done that frequently. -Original Message- From: shiv shivaji shivaji...@yahoo.com Sent: Sunday, February 28, 2010 3:34pm To: cassandra-user@incubator.apache.org Subject: Re: Anti-compaction Diskspace issue even when latest patch applied Seems like the temporary solution was to run a cron job which calls nodetool cleanup every 5 mins or so. This stopped the disk space from going too low. The manual solution you mentioned is likely worthy of consideration as the load balancing is taking a while. I will track the jira issue of anticompaction and diskspace. Thanks for the pointer. Thanks, Shiv From: Jonathan Ellis jbel...@gmail.com To: cassandra-user@incubator.apache.org Sent: Wed, February 24, 2010 11:34:59 AM Subject: Re: Anti-compaction Diskspace issue even when latest patch applied as you noticed, nodeprobe move first unloads the data, then moves to the new position. so that won't help you here. If you are using replicationfactor=1, scp the data to the previous node on the ring, then reduce the original node's token so it isn't responsible for so much, and run cleanup. (you can do this w/ higher RF too, you just have to scp the data more places.) Finally, you could work on https://issues.apache.org/jira/browse/CASSANDRA-579 so it doesn't need to anticompact to disk before moving data. -Jonathan On Wed, Feb 24, 2010 at 12:06 PM, shiv shivaji shivaji...@yahoo.com
Re: Anti-compaction Diskspace issue even when latest patch applied
On Fri, Mar 5, 2010 at 2:13 AM, shiv shivaji shivaji...@yahoo.com wrote: 1. Is there a way to estimate the time it would take to compact this work load? I hope the load balancing will be much faster after the compaction. Curious how fast I can get the transfer once compaction is done. 0.6 gives you compaction progress, so you can estimate from that. 2. Any way to make this faster? Is working on the above issue the lowest hanging fruit or is there something else? Not adding new data at the same time would probably make it faster, although you haven't told us where the bottleneck is. (http://spyced.blogspot.com/2010/01/linux-performance-basics.html) -Jonathan
Re: Anti-compaction Diskspace issue even when latest patch applied
Sorry, how to get compaction progress with 0.6. Is it in nodetool or somewhere else? I tried a few options after nodetool and did not get this info. My vmstats are procs ---memory-- ---swap-- -io -system-- cpu r b swpd free buff cache si sobibo in cs us sy id wa 1 0 2234752 85440 0 27270300 43 32 2562 3474 19 21 10 2 83 5 1 0 2234744 91220 0 27281208 100 24893 41788 10330 2482 10 2 81 6 2 0 2234732 102560 0 27271640 390 25230 21048 10300 2346 10 2 82 6 1 1 2234720 106660 0 2726819200 24730 34483 10700 2563 10 3 81 6 iostats: Linux 2.6.30-gentoo-r4pb (cl201) 03/05/10 _x86_64_(8 CPU) avg-cpu: %user %nice %system %iowait %steal %idle 9.620.002.174.950.00 83.26 Device:tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sda 126.60 7527.18 9843.04 1252414800 1637741619 sdb 96.95 6828.70 9348.09 1136197889 1555388186 sdc 96.82 6830.49 9324.74 1136496543 1551504064 sde 97.04 6830.45 9327.39 1136488926 1551944491 sdd 98.37 6829.08 9349.83 1136260775 1555678239 sdf 96.46 6828.30 9330.57 1136131741 1552473459 md0 1.9418.5927.9730927904653501 md22239.84 40960.19 55939.76 6815190175 9307575976 The md2 disk contains the data for cassandra. Regarding my previous reply, I do not mind working on the issue you mentioned, but have to get manager approval and if it best solves the problem, then great! So far, I am convinced it is related to compaction. Shiv From: Jonathan Ellis jbel...@gmail.com To: cassandra-user@incubator.apache.org Sent: Fri, March 5, 2010 9:00:19 AM Subject: Re: Anti-compaction Diskspace issue even when latest patch applied On Fri, Mar 5, 2010 at 2:13 AM, shiv shivaji shivaji...@yahoo.com wrote: 1. Is there a way to estimate the time it would take to compact this work load? I hope the load balancing will be much faster after the compaction. Curious how fast I can get the transfer once compaction is done. 0.6 gives you compaction progress, so you can estimate from that. 2. Any way to make this faster? Is working on the above issue the lowest hanging fruit or is there something else? Not adding new data at the same time would probably make it faster, although you haven't told us where the bottleneck is. (http://spyced.blogspot.com/2010/01/linux-performance-basics.html) -Jonathan
Re: Anti-compaction Diskspace issue even when latest patch applied
On Fri, Mar 5, 2010 at 1:36 PM, shiv shivaji shivaji...@yahoo.com wrote: Sorry, how to get compaction progress with 0.6. Is it in nodetool or somewhere else? I tried a few options after nodetool and did not get this info. it's under CompactionManager in jmx. I'm not sure if nodetool exposes this but it's easy to find in JConsole mbeans. iostats: what about iostat -x? -Jonathan
Re: Anti-compaction Diskspace issue even when latest patch applied
Ah, will look at the jmx console. Thought it was under nodetool. cont...@cl201 ~/swell/cassandra $ iostat -x Linux 2.6.30-gentoo-r4pb (cl201) 03/05/10 _x86_64_(8 CPU) avg-cpu: %user %nice %system %iowait %steal %idle 9.660.002.184.980.00 83.18 Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util sda 86.37 315.56 53.65 73.00 7534.09 9905.44 137.70 1.47 11.63 2.18 27.66 sdb 24.35 254.96 29.45 67.79 6842.55 9415.54 167.19 0.737.50 1.83 17.83 sdc 24.41 254.17 29.44 67.63 6844.34 9389.56 167.23 0.737.50 1.83 17.78 sde 24.73 254.26 29.44 67.87 6844.29 9392.18 166.86 0.636.50 1.81 17.63 sdd 24.38 254.82 29.44 69.24 6842.92 9417.35 164.76 0.757.58 1.83 18.01 sdf 24.35 254.57 29.36 67.37 6842.16 9397.45 167.88 0.697.18 1.83 17.68 md0 0.00 0.000.601.3118.6227.2124.00 0.000.00 0.00 0.00 md2 0.00 0.00 322.69 1932.98 41043.23 56337.8343.17 0.000.00 0.00 0.00 Shiv From: Jonathan Ellis jbel...@gmail.com To: cassandra-user@incubator.apache.org Sent: Fri, March 5, 2010 11:52:18 AM Subject: Re: Anti-compaction Diskspace issue even when latest patch applied On Fri, Mar 5, 2010 at 1:36 PM, shiv shivaji shivaji...@yahoo.com wrote: Sorry, how to get compaction progress with 0.6. Is it in nodetool or somewhere else? I tried a few options after nodetool and did not get this info. it's under CompactionManager in jmx. I'm not sure if nodetool exposes this but it's easy to find in JConsole mbeans. iostats: what about iostat -x? -Jonathan
Re: Anti-compaction Diskspace issue even when latest patch applied
Yes. The IP change trick seems to work. Load balancing seems a little slow, but I will open a new thread on that if needed. Thanks, Shiv From: Jonathan Ellis jbel...@gmail.com To: cassandra-user@incubator.apache.org Sent: Wed, March 3, 2010 9:21:28 AM Subject: Re: Anti-compaction Diskspace issue even when latest patch applied You are proposing manually moving your data from a 5TB disk to a 12TB disk, and that is the only change you want to make? Then just keep the IP the same when you restart it after moving, and you won't have to do anything else, it will just look like the node was down temporarily and is now back up. On Tue, Mar 2, 2010 at 7:26 PM, shiv shivaji shivaji...@yahoo.com wrote: Thanks, just realized this after looking at the source code. Seems like the decommission will not work for me due to disk space issues. I am currently moving all the data on the heavy node (5 TB full) to a 12 TB disk drive. I am planning to remove the old token and resign the old token to this node. According to the docs, it says to use decommission, however lack of disk space does not allow me to do this. If I manually move all the data files and then do a removetoken and start the node with a new token, would that work (as was implied in a JIRA)? Shiv From: Stu Hood stu.h...@rackspace.com To: cassandra-user@incubator.apache.org Sent: Sun, February 28, 2010 1:53:29 PM Subject: Re: Anti-compaction Diskspace issue even when latest patch applied `nodetool cleanup` is a very expensive process: it performs a major compaction, and should not be done that frequently. -Original Message- From: shiv shivaji shivaji...@yahoo.com Sent: Sunday, February 28, 2010 3:34pm To: cassandra-user@incubator.apache.org Subject: Re: Anti-compaction Diskspace issue even when latest patch applied Seems like the temporary solution was to run a cron job which calls nodetool cleanup every 5 mins or so. This stopped the disk space from going too low. The manual solution you mentioned is likely worthy of consideration as the load balancing is taking a while. I will track the jira issue of anticompaction and diskspace. Thanks for the pointer. Thanks, Shiv From: Jonathan Ellis jbel...@gmail.com To: cassandra-user@incubator.apache.org Sent: Wed, February 24, 2010 11:34:59 AM Subject: Re: Anti-compaction Diskspace issue even when latest patch applied as you noticed, nodeprobe move first unloads the data, then moves to the new position. so that won't help you here. If you are using replicationfactor=1, scp the data to the previous node on the ring, then reduce the original node's token so it isn't responsible for so much, and run cleanup. (you can do this w/ higher RF too, you just have to scp the data more places.) Finally, you could work on https://issues.apache.org/jira/browse/CASSANDRA-579 so it doesn't need to anticompact to disk before moving data. -Jonathan On Wed, Feb 24, 2010 at 12:06 PM, shiv shivaji shivaji...@yahoo.com wrote: According to the stack trace I get in the log, it makes it look like the patch was for anti-compaction but I did not look at the source code in detail yet. java.util.concurrent.ExecutionException: java.lang.UnsupportedOperationException: disk full at java.util.concurrent.FutureTask$Sync.innerGet(FutureTask.java:222) at java.util.concurrent.FutureTask.get(FutureTask.java:83) at org.apache.cassandra.concurrent.DebuggableThreadPoolExecutor.afterExecute(DebuggableThreadPoolExecutor.java:86) at org.apache.cassandra.db.CompactionManager$CompactionExecutor.afterExecute(CompactionManager.java:570) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:888) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:619) Caused by: java.lang.UnsupportedOperationException: disk full at org.apache.cassandra.db.CompactionManager.doAntiCompaction(CompactionManager.java:344) at org.apache.cassandra.db.CompactionManager.doCleanupCompaction(CompactionManager.java:405) at org.apache.cassandra.db.CompactionManager.access$400(CompactionManager.java:49) at org.apache.cassandra.db.CompactionManager$2.call(CompactionManager.java:130) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) at java.util.concurrent.FutureTask.run(FutureTask.java:138) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) ... 2 more I tried nodetool cleanup before and it did not really stop the disk from filling, is there a way to force move the data or some other way to solve the issue? Thanks, Shiv From: Jonathan Ellis jbel...@gmail.com To: cassandra-user
Re: Anti-compaction Diskspace issue even when latest patch applied
https://issues.apache.org/jira/browse/CASSANDRA-579 should make a big difference in speed. If you want to take a stab at it I can point you in the right direction. :) On Thu, Mar 4, 2010 at 10:24 AM, shiv shivaji shivaji...@yahoo.com wrote: Yes. The IP change trick seems to work. Load balancing seems a little slow, but I will open a new thread on that if needed. Thanks, Shiv From: Jonathan Ellis jbel...@gmail.com To: cassandra-user@incubator.apache.org Sent: Wed, March 3, 2010 9:21:28 AM Subject: Re: Anti-compaction Diskspace issue even when latest patch applied You are proposing manually moving your data from a 5TB disk to a 12TB disk, and that is the only change you want to make? Then just keep the IP the same when you restart it after moving, and you won't have to do anything else, it will just look like the node was down temporarily and is now back up. On Tue, Mar 2, 2010 at 7:26 PM, shiv shivaji shivaji...@yahoo.com wrote: Thanks, just realized this after looking at the source code. Seems like the decommission will not work for me due to disk space issues. I am currently moving all the data on the heavy node (5 TB full) to a 12 TB disk drive. I am planning to remove the old token and resign the old token to this node. According to the docs, it says to use decommission, however lack of disk space does not allow me to do this. If I manually move all the data files and then do a removetoken and start the node with a new token, would that work (as was implied in a JIRA)? Shiv From: Stu Hood stu.h...@rackspace.com To: cassandra-user@incubator.apache.org Sent: Sun, February 28, 2010 1:53:29 PM Subject: Re: Anti-compaction Diskspace issue even when latest patch applied `nodetool cleanup` is a very expensive process: it performs a major compaction, and should not be done that frequently. -Original Message- From: shiv shivaji shivaji...@yahoo.com Sent: Sunday, February 28, 2010 3:34pm To: cassandra-user@incubator.apache.org Subject: Re: Anti-compaction Diskspace issue even when latest patch applied Seems like the temporary solution was to run a cron job which calls nodetool cleanup every 5 mins or so. This stopped the disk space from going too low. The manual solution you mentioned is likely worthy of consideration as the load balancing is taking a while. I will track the jira issue of anticompaction and diskspace. Thanks for the pointer. Thanks, Shiv From: Jonathan Ellis jbel...@gmail.com To: cassandra-user@incubator.apache.org Sent: Wed, February 24, 2010 11:34:59 AM Subject: Re: Anti-compaction Diskspace issue even when latest patch applied as you noticed, nodeprobe move first unloads the data, then moves to the new position. so that won't help you here. If you are using replicationfactor=1, scp the data to the previous node on the ring, then reduce the original node's token so it isn't responsible for so much, and run cleanup. (you can do this w/ higher RF too, you just have to scp the data more places.) Finally, you could work on https://issues.apache.org/jira/browse/CASSANDRA-579 so it doesn't need to anticompact to disk before moving data. -Jonathan On Wed, Feb 24, 2010 at 12:06 PM, shiv shivaji shivaji...@yahoo.com wrote: According to the stack trace I get in the log, it makes it look like the patch was for anti-compaction but I did not look at the source code in detail yet. java.util.concurrent.ExecutionException: java.lang.UnsupportedOperationException: disk full at java.util.concurrent.FutureTask$Sync.innerGet(FutureTask.java:222) at java.util.concurrent.FutureTask.get(FutureTask.java:83) at org.apache.cassandra.concurrent.DebuggableThreadPoolExecutor.afterExecute(DebuggableThreadPoolExecutor.java:86) at org.apache.cassandra.db.CompactionManager$CompactionExecutor.afterExecute(CompactionManager.java:570) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:888) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:619) Caused by: java.lang.UnsupportedOperationException: disk full at org.apache.cassandra.db.CompactionManager.doAntiCompaction(CompactionManager.java:344) at org.apache.cassandra.db.CompactionManager.doCleanupCompaction(CompactionManager.java:405) at org.apache.cassandra.db.CompactionManager.access$400(CompactionManager.java:49) at org.apache.cassandra.db.CompactionManager$2.call(CompactionManager.java:130) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) at java.util.concurrent.FutureTask.run(FutureTask.java:138) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) ... 2 more I
Re: Anti-compaction Diskspace issue even when latest patch applied
You are proposing manually moving your data from a 5TB disk to a 12TB disk, and that is the only change you want to make? Then just keep the IP the same when you restart it after moving, and you won't have to do anything else, it will just look like the node was down temporarily and is now back up. On Tue, Mar 2, 2010 at 7:26 PM, shiv shivaji shivaji...@yahoo.com wrote: Thanks, just realized this after looking at the source code. Seems like the decommission will not work for me due to disk space issues. I am currently moving all the data on the heavy node (5 TB full) to a 12 TB disk drive. I am planning to remove the old token and resign the old token to this node. According to the docs, it says to use decommission, however lack of disk space does not allow me to do this. If I manually move all the data files and then do a removetoken and start the node with a new token, would that work (as was implied in a JIRA)? Shiv From: Stu Hood stu.h...@rackspace.com To: cassandra-user@incubator.apache.org Sent: Sun, February 28, 2010 1:53:29 PM Subject: Re: Anti-compaction Diskspace issue even when latest patch applied `nodetool cleanup` is a very expensive process: it performs a major compaction, and should not be done that frequently. -Original Message- From: shiv shivaji shivaji...@yahoo.com Sent: Sunday, February 28, 2010 3:34pm To: cassandra-user@incubator.apache.org Subject: Re: Anti-compaction Diskspace issue even when latest patch applied Seems like the temporary solution was to run a cron job which calls nodetool cleanup every 5 mins or so. This stopped the disk space from going too low. The manual solution you mentioned is likely worthy of consideration as the load balancing is taking a while. I will track the jira issue of anticompaction and diskspace. Thanks for the pointer. Thanks, Shiv From: Jonathan Ellis jbel...@gmail.com To: cassandra-user@incubator.apache.org Sent: Wed, February 24, 2010 11:34:59 AM Subject: Re: Anti-compaction Diskspace issue even when latest patch applied as you noticed, nodeprobe move first unloads the data, then moves to the new position. so that won't help you here. If you are using replicationfactor=1, scp the data to the previous node on the ring, then reduce the original node's token so it isn't responsible for so much, and run cleanup. (you can do this w/ higher RF too, you just have to scp the data more places.) Finally, you could work on https://issues.apache.org/jira/browse/CASSANDRA-579 so it doesn't need to anticompact to disk before moving data. -Jonathan On Wed, Feb 24, 2010 at 12:06 PM, shiv shivaji shivaji...@yahoo.com wrote: According to the stack trace I get in the log, it makes it look like the patch was for anti-compaction but I did not look at the source code in detail yet. java.util.concurrent.ExecutionException: java.lang.UnsupportedOperationException: disk full at java.util.concurrent.FutureTask$Sync.innerGet(FutureTask.java:222) at java.util.concurrent.FutureTask.get(FutureTask.java:83) at org.apache.cassandra.concurrent.DebuggableThreadPoolExecutor.afterExecute(DebuggableThreadPoolExecutor.java:86) at org.apache.cassandra.db.CompactionManager$CompactionExecutor.afterExecute(CompactionManager.java:570) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:888) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:619) Caused by: java.lang.UnsupportedOperationException: disk full at org.apache.cassandra.db.CompactionManager.doAntiCompaction(CompactionManager.java:344) at org.apache.cassandra.db.CompactionManager.doCleanupCompaction(CompactionManager.java:405) at org.apache.cassandra.db.CompactionManager.access$400(CompactionManager.java:49) at org.apache.cassandra.db.CompactionManager$2.call(CompactionManager.java:130) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) at java.util.concurrent.FutureTask.run(FutureTask.java:138) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) ... 2 more I tried nodetool cleanup before and it did not really stop the disk from filling, is there a way to force move the data or some other way to solve the issue? Thanks, Shiv From: Jonathan Ellis jbel...@gmail.com To: cassandra-user@incubator.apache.org Sent: Wed, February 24, 2010 7:16:32 AM Subject: Re: Anti-compaction Diskspace issue even when latest patch applied The patch you refer to was to help *compaction*, not *anticompaction*. If the space is mostly hints for other machines (is that what you meant by due to past problems with others?) you should run nodeprobe cleanup on it to remove
