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.
