Hi Frederik, Did you figure out a solution to this problem?
I'm asking because I recently ran into a similar problem, with a similar setup (8 shards on one server). Occasionally a query will take a very long time. Occasionally I see timeout exceptions with the HTTP requests. E.g. > 348914 [pool-19-thread-14] INFO > org.apache.commons.httpclient.HttpMethodDirector - I/O exception > (org.apache.commons.httpclient.NoHttpResponseException) caught when > processing request: The > server localhost failed to respond > 348915 [pool-19-thread-14] INFO > org.apache.commons.httpclient.HttpMethodDirector - Retrying request Restarting Jetty seems to clear up the problem temporarily. I've been looking at the code in Solr that handles distributed requests - and it's got some interesting smells, so I wouldn't be surprised if there's an issue related to how it's using HttpClient. Regards, -- Ken On Sep 28, 2011, at 5:21am, Frederik Kraus wrote: > I just had a look at the thread-dump, pasting 3 examples here: > > > 'pool-31-thread-8233' Id=11626, BLOCKED on > lock=org.apache.commons.httpclient.MultiThreadedHttpConnectionManager$ConnectionPool@19dd10d9, > total cpu time=20.0000ms user time=20.0000ms > at > org.apache.commons.httpclient.MultiThreadedHttpConnectionManager$ConnectionPool.freeConnection(MultiThreadedHttpConnectionManager.java:982) > > at > org.apache.commons.httpclient.MultiThreadedHttpConnectionManager.releaseConnection(MultiThreadedHttpConnectionManager.java:643) > > at > org.apache.commons.httpclient.HttpConnection.releaseConnection(HttpConnection.java:1179) > > at > org.apache.commons.httpclient.MultiThreadedHttpConnectionManager$HttpConnectionAdapter.releaseConnection(MultiThreadedHttpConnectionManager.java:1423) > > at > org.apache.commons.httpclient.HttpMethodBase.ensureConnectionRelease(HttpMethodBase.java:2430) > > at > org.apache.commons.httpclient.HttpMethodBase.responseBodyConsumed(HttpMethodBase.java:2422) > > at > org.apache.commons.httpclient.HttpMethodBase$1.responseConsumed(HttpMethodBase.java:1892) > > at > org.apache.commons.httpclient.AutoCloseInputStream.notifyWatcher(AutoCloseInputStream.java:198) > > at > org.apache.commons.httpclient.AutoCloseInputStream.close(AutoCloseInputStream.java:158) > > at > org.apache.commons.httpclient.HttpMethodBase.releaseConnection(HttpMethodBase.java:1181) > > at > org.apache.solr.client.solrj.impl.CommonsHttpSolrServer.request(CommonsHttpSolrServer.java:486) > > at > org.apache.solr.client.solrj.impl.CommonsHttpSolrServer.request(CommonsHttpSolrServer.java:244) > > at > org.apache.solr.handler.component.HttpCommComponent$1.call(SearchHandler.java:421) > > at > org.apache.solr.handler.component.HttpCommComponent$1.call(SearchHandler.java:393) > > at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) > at java.util.concurrent.FutureTask.run(FutureTask.java:138) > 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$Worker.runTask(ThreadPoolExecutor.java:886) > > at > java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) > > at java.lang.Thread.run(Thread.java:662) > > 'pool-31-thread-8232' Id=11625, BLOCKED on > lock=org.apache.commons.httpclient.MultiThreadedHttpConnectionManager$ConnectionPool@19dd10d9, > total cpu time=20.0000ms user time=20.0000ms > at > org.apache.commons.httpclient.MultiThreadedHttpConnectionManager.doGetConnection(MultiThreadedHttpConnectionManager.java:447) > > at > org.apache.commons.httpclient.MultiThreadedHttpConnectionManager.getConnectionWithTimeout(MultiThreadedHttpConnectionManager.java:416) > > at > org.apache.commons.httpclient.HttpMethodDirector.executeMethod(HttpMethodDirector.java:153) > > at > org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:397) > at > org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:323) > at > org.apache.solr.client.solrj.impl.CommonsHttpSolrServer.request(CommonsHttpSolrServer.java:427) > > at > org.apache.solr.client.solrj.impl.CommonsHttpSolrServer.request(CommonsHttpSolrServer.java:244) > > at > org.apache.solr.handler.component.HttpCommComponent$1.call(SearchHandler.java:421) > > at > org.apache.solr.handler.component.HttpCommComponent$1.call(SearchHandler.java:393) > > at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) > at java.util.concurrent.FutureTask.run(FutureTask.java:138) > 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$Worker.runTask(ThreadPoolExecutor.java:886) > > at > java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) > > at java.lang.Thread.run(Thread.java:662) > and > > 'http-8080-381' Id=6859, WAITING on > lock=java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject@2607b720, > total cpu time=990.0000ms user time=920.0000ms > > at sun.misc.Unsafe.park(Native Method) > at java.util.concurrent.locks.LockSupport.park(LockSupport.java:158) > at > java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1987) > > at > java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:399) > at > java.util.concurrent.ExecutorCompletionService.take(ExecutorCompletionService.java:164) > > at > org.apache.solr.handler.component.HttpCommComponent.takeCompletedOrError(SearchHandler.java:469) > > at > org.apache.solr.handler.component.SearchHandler.handleRequestBody(SearchHandler.java:271) > > at > org.apache.solr.handler.RequestHandlerBase.handleRequest(RequestHandlerBase.java:129) > > at org.apache.solr.core.SolrCore.execute(SolrCore.java:1368) > at > org.apache.solr.servlet.SolrDispatchFilter.execute(SolrDispatchFilter.java:356) > > at > org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:252) > > at > org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) > > at > org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) > > at > org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) > > at > org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) > > at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:554) > at > org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) > at > org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) > at > org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) > > at > org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298) > at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859) > at > org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588) > > at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489) > at java.lang.Thread.run(Thread.java:662) > > > > > > > Am Mittwoch, 28. September 2011 um 13:53 schrieb Frederik Kraus: > >> >> >> Am Mittwoch, 28. September 2011 um 13:41 schrieb Vadim Kisselmann: >> >>> Hi Fred, >>> >>> ok, it's a strange behavior with same queries. >>> Another questions: >>> -which solr version? >> >> 3.3 (might the NIOFSDirectory from 3.4 help?) >> >>> -do you indexing during your load test? (because of index rebuilt) >> nope >> >>> -do you replicate your index? >> >> nope >>> >>> Regards >>> Vadim >>> >>> >>> >>> 2011/9/28 Frederik Kraus <frederik.kr...@gmail.com >>> (mailto:frederik.kr...@gmail.com)> >>> >>>> Hi Vladim, >>>> >>>> the thing is, that those exact same queries, that take longer during a load >>>> test, perform just fine when executed at a slower request rate and are also >>>> random, i.e. there is no pattern in bad/slow queries. >>>> >>>> My first thought was some kind of contention and/or connection starvation >>>> for the internal shard communication? >>>> >>>> Fred. >>>> >>>> >>>> Am Mittwoch, 28. September 2011 um 13:18 schrieb Vadim Kisselmann: >>>> >>>>> Hi Fred, >>>>> analyze the queries which take longer. >>>>> We observe our queries and see the problems with q-time with queries >>>> which >>>>> are complex, with phrase queries or queries which contains numbers or >>>>> special characters. >>>>> if you don't know it: >>>> http://www.hathitrust.org/blogs/large-scale-search/tuning-search-performance >>>>> Regards >>>>> Vadim >>>>> >>>>> >>>>> 2011/9/28 Frederik Kraus <frederik.kr...@gmail.com >>>>> (mailto:frederik.kr...@gmail.com) (mailto: >>>> frederik.kr...@gmail.com (mailto:frederik.kr...@gmail.com))> >>>>> >>>>>> Hi, >>>>>> >>>>>> >>>>>> I am experiencing a strange issue doing some load tests. Our setup: >>>>>> >>>>>> - 2 server with each 24 cpu cores, 130GB of RAM >>>>>> - 10 shards per server (needed for response times) running in a single >>>>>> tomcat instance >>>>>> - each query queries all 20 shards (distributed search) >>>>>> >>>>>> - each shard holds about 1.5 mio documents (small shards are needed due >>>> to >>>>>> rather complex queries) >>>>>> - all caches are warmed / high cache hit rates (99%) etc. >>>>>> >>>>>> >>>>>> Now for some reason we cannot seem to fully utilize all CPU power (no >>>> disk >>>>>> IO), ie. increasing concurrent users doesn't increase CPU-Load at a >>>> point, >>>>>> decreases throughput and increases the response times of the individual >>>>>> queries. >>>>>> >>>>>> Also 1-2% of the queries take significantly longer: avg somewhere at >>>> 100ms >>>>>> while 1-2% take 1.5s or longer. >>>>>> >>>>>> Any ideas are greatly appreciated :) >>>>>> >>>>>> Fred. > -------------------------- Ken Krugler http://www.scaleunlimited.com custom big data solutions & training Hadoop, Cascading, Mahout & Solr
