Okay, thanks, useful info. Getting on a plane, but ill look more at this soon. That 10k thread spike is good to know - that's no good and could easily be part of the problem. We want to keep that from happening.
Mark Sent from my iPhone On Sep 6, 2013, at 2:05 PM, Tim Vaillancourt <t...@elementspace.com> wrote: > Hey Mark, > > The farthest we've made it at the same batch size/volume was 12 hours > without this patch, but that isn't consistent. Sometimes we would only get > to 6 hours or less. > > During the crash I can see an amazing spike in threads to 10k which is > essentially our ulimit for the JVM, but I strangely see no "OutOfMemory: > cannot open native thread errors" that always follow this. Weird! > > We also notice a spike in CPU around the crash. The instability caused some > shard recovery/replication though, so that CPU may be a symptom of the > replication, or is possibly the root cause. The CPU spikes from about > 20-30% utilization (system + user) to 60% fairly sharply, so the CPU, while > spiking isn't quite "pinned" (very beefy Dell R720s - 16 core Xeons, whole > index is in 128GB RAM, 6xRAID10 15k). > > More on resources: our disk I/O seemed to spike about 2x during the crash > (about 1300kbps written to 3500kbps), but this may have been the > replication, or ERROR logging (we generally log nothing due to > WARN-severity unless something breaks). > > Lastly, I found this stack trace occurring frequently, and have no idea > what it is (may be useful or not): > > "java.lang.IllegalStateException : > at org.eclipse.jetty.server.Response.resetBuffer(Response.java:964) > at org.eclipse.jetty.server.Response.sendError(Response.java:325) > at > org.apache.solr.servlet.SolrDispatchFilter.sendError(SolrDispatchFilter.java:692) > at > org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:380) > at > org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:155) > at > org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1423) > at > org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:450) > at > org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:138) > at > org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:564) > at > org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:213) > at > org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1083) > at > org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:379) > at > org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:175) > at > org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1017) > at > org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:136) > at > org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:258) > at > org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:109) > at > org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97) > at org.eclipse.jetty.server.Server.handle(Server.java:445) > at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:260) > at > org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:225) > at > org.eclipse.jetty.io.AbstractConnection$ReadCallback.run(AbstractConnection.java:358) > at > org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:596) > at > org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:527) > at java.lang.Thread.run(Thread.java:724)" > > On your live_nodes question, I don't have historical data on this from when > the crash occurred, which I guess is what you're looking for. I could add > this to our monitoring for future tests, however. I'd be glad to continue > further testing, but I think first more monitoring is needed to understand > this further. Could we come up with a list of metrics that would be useful > to see following another test and successful crash? > > Metrics needed: > > 1) # of live_nodes. > 2) Full stack traces. > 3) CPU used by Solr's JVM specifically (instead of system-wide). > 4) Solr's JVM thread count (already done) > 5) ? > > Cheers, > > Tim Vaillancourt > > > On 6 September 2013 13:11, Mark Miller <markrmil...@gmail.com> wrote: > >> Did you ever get to index that long before without hitting the deadlock? >> >> There really isn't anything negative the patch could be introducing, other >> than allowing for some more threads to possibly run at once. If I had to >> guess, I would say its likely this patch fixes the deadlock issue and your >> seeing another issue - which looks like the system cannot keep up with the >> requests or something for some reason - perhaps due to some OS networking >> settings or something (more guessing). Connection refused happens generally >> when there is nothing listening on the port. >> >> Do you see anything interesting change with the rest of the system? CPU >> usage spikes or something like that? >> >> Clamping down further on the overall number of threads night help (which >> would require making something configurable). How many nodes are listed in >> zk under live_nodes? >> >> Mark >> >> Sent from my iPhone >> >> On Sep 6, 2013, at 12:02 PM, Tim Vaillancourt <t...@elementspace.com> >> wrote: >> >>> Hey guys, >>> >>> (copy of my post to SOLR-5216) >>> >>> We tested this patch and unfortunately encountered some serious issues a >>> few hours of 500 update-batches/sec. Our update batch is 10 docs, so we >> are >>> writing about 5000 docs/sec total, using autoCommit to commit the updates >>> (no explicit commits). >>> >>> Our environment: >>> >>> Solr 4.3.1 w/SOLR-5216 patch. >>> Jetty 9, Java 1.7. >>> 3 solr instances, 1 per physical server. >>> 1 collection. >>> 3 shards. >>> 2 replicas (each instance is a leader and a replica). >>> Soft autoCommit is 1000ms. >>> Hard autoCommit is 15000ms. >>> >>> After about 6 hours of stress-testing this patch, we see many of these >>> stalled transactions (below), and the Solr instances start to see each >>> other as down, flooding our Solr logs with "Connection Refused" >> exceptions, >>> and otherwise no obviously-useful logs that I could see. >>> >>> I did notice some stalled transactions on both /select and /update, >>> however. This never occurred without this patch. >>> >>> Stack /select seems stalled on: http://pastebin.com/Y1NCrXGC >>> Stack /update seems stalled on: http://pastebin.com/cFLbC8Y9 >>> >>> Lastly, I have a summary of the ERROR-severity logs from this 24-hour >> soak. >>> My script "normalizes" the ERROR-severity stack traces and returns them >> in >>> order of occurrence. >>> >>> Summary of my solr.log: http://pastebin.com/pBdMAWeb >>> >>> Thanks! >>> >>> Tim Vaillancourt >>> >>> >>> On 6 September 2013 07:27, Markus Jelsma <markus.jel...@openindex.io> >> wrote: >>> >>>> Thanks! >>>> >>>> -----Original message----- >>>>> From:Erick Erickson <erickerick...@gmail.com> >>>>> Sent: Friday 6th September 2013 16:20 >>>>> To: solr-user@lucene.apache.org >>>>> Subject: Re: SolrCloud 4.x hangs under high update volume >>>>> >>>>> Markus: >>>>> >>>>> See: https://issues.apache.org/jira/browse/SOLR-5216 >>>>> >>>>> >>>>> On Wed, Sep 4, 2013 at 11:04 AM, Markus Jelsma >>>>> <markus.jel...@openindex.io>wrote: >>>>> >>>>>> Hi Mark, >>>>>> >>>>>> Got an issue to watch? >>>>>> >>>>>> Thanks, >>>>>> Markus >>>>>> >>>>>> -----Original message----- >>>>>>> From:Mark Miller <markrmil...@gmail.com> >>>>>>> Sent: Wednesday 4th September 2013 16:55 >>>>>>> To: solr-user@lucene.apache.org >>>>>>> Subject: Re: SolrCloud 4.x hangs under high update volume >>>>>>> >>>>>>> I'm going to try and fix the root cause for 4.5 - I've suspected >>>> what it >>>>>> is since early this year, but it's never personally been an issue, so >>>> it's >>>>>> rolled along for a long time. >>>>>>> >>>>>>> Mark >>>>>>> >>>>>>> Sent from my iPhone >>>>>>> >>>>>>> On Sep 3, 2013, at 4:30 PM, Tim Vaillancourt <t...@elementspace.com> >>>>>> wrote: >>>>>>> >>>>>>>> Hey guys, >>>>>>>> >>>>>>>> I am looking into an issue we've been having with SolrCloud since >>>> the >>>>>>>> beginning of our testing, all the way from 4.1 to 4.3 (haven't >>>> tested >>>>>> 4.4.0 >>>>>>>> yet). I've noticed other users with this same issue, so I'd really >>>>>> like to >>>>>>>> get to the bottom of it. >>>>>>>> >>>>>>>> Under a very, very high rate of updates (2000+/sec), after 1-12 >>>> hours >>>>>> we >>>>>>>> see stalled transactions that snowball to consume all Jetty >>>> threads in >>>>>> the >>>>>>>> JVM. This eventually causes the JVM to hang with most threads >>>> waiting >>>>>> on >>>>>>>> the condition/stack provided at the bottom of this message. At this >>>>>> point >>>>>>>> SolrCloud instances then start to see their neighbors (who also >>>> have >>>>>> all >>>>>>>> threads hung) as down w/"Connection Refused", and the shards become >>>>>> "down" >>>>>>>> in state. Sometimes a node or two survives and just returns 503s >>>> "no >>>>>> server >>>>>>>> hosting shard" errors. >>>>>>>> >>>>>>>> As a workaround/experiment, we have tuned the number of threads >>>> sending >>>>>>>> updates to Solr, as well as the batch size (we batch updates from >>>>>> client -> >>>>>>>> solr), and the Soft/Hard autoCommits, all to no avail. Turning off >>>>>>>> Client-to-Solr batching (1 update = 1 call to Solr), which also >>>> did not >>>>>>>> help. Certain combinations of update threads and batch sizes seem >>>> to >>>>>>>> mask/help the problem, but not resolve it entirely. >>>>>>>> >>>>>>>> Our current environment is the following: >>>>>>>> - 3 x Solr 4.3.1 instances in Jetty 9 w/Java 7. >>>>>>>> - 3 x Zookeeper instances, external Java 7 JVM. >>>>>>>> - 1 collection, 3 shards, 2 replicas (each node is a leader of 1 >>>> shard >>>>>> and >>>>>>>> a replica of 1 shard). >>>>>>>> - Log4j 1.2 for Solr logs, set to WARN. This log has no movement >>>> on a >>>>>> good >>>>>>>> day. >>>>>>>> - 5000 max jetty threads (well above what we use when we are >>>> healthy), >>>>>>>> Linux-user threads ulimit is 6000. >>>>>>>> - Occurs under Jetty 8 or 9 (many versions). >>>>>>>> - Occurs under Java 1.6 or 1.7 (several minor versions). >>>>>>>> - Occurs under several JVM tunings. >>>>>>>> - Everything seems to point to Solr itself, and not a Jetty or Java >>>>>> version >>>>>>>> (I hope I'm wrong). >>>>>>>> >>>>>>>> The stack trace that is holding up all my Jetty QTP threads is the >>>>>>>> following, which seems to be waiting on a lock that I would very >>>> much >>>>>> like >>>>>>>> to understand further: >>>>>>>> >>>>>>>> "java.lang.Thread.State: WAITING (parking) >>>>>>>> at sun.misc.Unsafe.park(Native Method) >>>>>>>> - parking to wait for <0x00000007216e68d8> (a >>>>>>>> java.util.concurrent.Semaphore$NonfairSync) >>>>>>>> at >>>> java.util.concurrent.locks.LockSupport.park(LockSupport.java:186) >>>>>>>> at >> java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:834) >>>>>>>> at >> java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:994) >>>>>>>> at >> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1303) >>>>>>>> at java.util.concurrent.Semaphore.acquire(Semaphore.java:317) >>>>>>>> at >> org.apache.solr.util.AdjustableSemaphore.acquire(AdjustableSemaphore.java:61) >>>>>>>> at >> org.apache.solr.update.SolrCmdDistributor.submit(SolrCmdDistributor.java:418) >>>>>>>> at >> org.apache.solr.update.SolrCmdDistributor.submit(SolrCmdDistributor.java:368) >>>>>>>> at >> org.apache.solr.update.SolrCmdDistributor.flushAdds(SolrCmdDistributor.java:300) >>>>>>>> at >> org.apache.solr.update.SolrCmdDistributor.finish(SolrCmdDistributor.java:96) >>>>>>>> at >> org.apache.solr.update.processor.DistributedUpdateProcessor.doFinish(DistributedUpdateProcessor.java:462) >>>>>>>> at >> org.apache.solr.update.processor.DistributedUpdateProcessor.finish(DistributedUpdateProcessor.java:1178) >>>>>>>> at >> org.apache.solr.handler.ContentStreamHandlerBase.handleRequestBody(ContentStreamHandlerBase.java:83) >>>>>>>> at >> org.apache.solr.handler.RequestHandlerBase.handleRequest(RequestHandlerBase.java:135) >>>>>>>> at org.apache.solr.core.SolrCore.execute(SolrCore.java:1820) >>>>>>>> at >> org.apache.solr.servlet.SolrDispatchFilter.execute(SolrDispatchFilter.java:656) >>>>>>>> at >> org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:359) >>>>>>>> at >> org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:155) >>>>>>>> at >> org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1486) >>>>>>>> at >> org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:503) >>>>>>>> at >> org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:138) >>>>>>>> at >> org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:564) >>>>>>>> at >> org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:213) >>>>>>>> at >> org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1096) >>>>>>>> at >> org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:432) >>>>>>>> at >> org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:175) >>>>>>>> at >> org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1030) >>>>>>>> at >> org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:136) >>>>>>>> at >> org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:201) >>>>>>>> at >> org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:109) >>>>>>>> at >> org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97) >>>>>>>> at org.eclipse.jetty.server.Server.handle(Server.java:445) >>>>>>>> at >>>> org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:268) >>>>>>>> at >> org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:229) >>>>>>>> at >> org.eclipse.jetty.io.AbstractConnection$ReadCallback.run(AbstractConnection.java:358) >>>>>>>> at >> org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:601) >>>>>>>> at >> org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:532) >>>>>>>> at java.lang.Thread.run(Thread.java:724)" >>>>>>>> >>>>>>>> Some questions I had were: >>>>>>>> 1) What exclusive locks does SolrCloud "make" when performing an >>>>>> update? >>>>>>>> 2) Keeping in mind I do not read or write java (sorry :D), could >>>>>> someone >>>>>>>> help me understand "what" solr is locking in this case at >> "org.apache.solr.util.AdjustableSemaphore.acquire(AdjustableSemaphore.java:61)" >>>>>>>> when performing an update? That will help me understand where to >>>> look >>>>>> next. >>>>>>>> 3) It seems all threads in this state are waiting for >>>>>> "0x00000007216e68d8", >>>>>>>> is there a way to tell what "0x00000007216e68d8" is? >>>>>>>> 4) Is there a limit to how many updates you can do in SolrCloud? >>>>>>>> 5) Wild-ass-theory: would more shards provide more locks (whatever >>>> they >>>>>>>> are) on update, and thus more update throughput? >>>>>>>> >>>>>>>> To those interested, I've provided a stacktrace of 1 of 3 nodes at >>>>>> this URL >>>>>>>> in gzipped form: >> https://s3.amazonaws.com/timvaillancourt.com/tmp/solr-jstack-2013-08-23.gz >>>>>>>> >>>>>>>> Any help/suggestions/ideas on this issue, big or small, would be >>>> much >>>>>>>> appreciated. >>>>>>>> >>>>>>>> Thanks so much all! >>>>>>>> >>>>>>>> Tim Vaillancourt >>
