Eu tenho um problema com meu ambiente Java. Estou executando o Solr 1.3 (mecanismo de pesquisa) há mais de um ano e, de repente, tive muitos problemas com ele. Todo o meu pool de threads (250) foi bloqueado aleatoriamente uma ou duas vezes por dia. Não fiz nenhuma alteração no meu aplicativo solr ou no meu servidor tomcat.

Estou executando o tomcat 5.5.25 e o Solr 1.3. Recebi um despejo de thread quando o sistema está totalmente sobrecarregado:

igot como 240 tópicos como este:

"http-8080-Processor1" daemon prio=10 tid=0x0000000000b2e000 nid=0x193 waiting for monitor entry [0x000000004066c000..0x000000004066cb20]
   java.lang.Thread.State: BLOCKED (on object monitor)
    at java.util.logging.StreamHandler.publish(StreamHandler.java:174)
    - waiting to lock <0x00007fe37e72b340> (a java.util.logging.ConsoleHandler)
    at java.util.logging.ConsoleHandler.publish(ConsoleHandler.java:88)
    at java.util.logging.Logger.log(Logger.java:472)
    at java.util.logging.Logger.doLog(Logger.java:494)
    at java.util.logging.Logger.log(Logger.java:517)
    at java.util.logging.Logger.info(Logger.java:1036)
    at org.apache.solr.core.SolrCore.execute(SolrCore.java:1212)
    at org.apache.solr.servlet.SolrDispatchFilter.execute(SolrDispatchFilter.java:303)
    at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:232)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:172)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:151)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:874)
    at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:665)
    at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:528)
    at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:81)
    at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:689)
    at java.lang.Thread.run(Thread.java:619)

Podemos ver que esse encadeamento está bloqueado e aguardando: <0x00007fe37e72b340>

O thread que realmente possui o <0x00007fe37e72b340> é este:

"http-8080-Processor156" daemon prio=10 tid=0x0000000000df2000 nid=0x1e52 runnable [0x0000000044521000..0x0000000044521c20]
   java.lang.Thread.State: RUNNABLE
    at java.io.FileOutputStream.writeBytes(Native Method)
    at java.io.FileOutputStream.write(FileOutputStream.java:260)
    at java.io.BufferedOutputStream.write(BufferedOutputStream.java:105)
    - locked <0x00007fe37e3abcd8> (a java.io.BufferedOutputStream)
    at java.io.PrintStream.write(PrintStream.java:430)
    - locked <0x00007fe37e3abca0> (a java.io.PrintStream)
    at sun.nio.cs.StreamEncoder.writeBytes(StreamEncoder.java:202)
    at sun.nio.cs.StreamEncoder.implFlushBuffer(StreamEncoder.java:272)
    at sun.nio.cs.StreamEncoder.implFlush(StreamEncoder.java:276)
    at sun.nio.cs.StreamEncoder.flush(StreamEncoder.java:122)
    - locked <0x00007fe37e72cd90> (a java.io.OutputStreamWriter)
    at java.io.OutputStreamWriter.flush(OutputStreamWriter.java:212)
    at java.util.logging.StreamHandler.flush(StreamHandler.java:225)
    - locked <0x00007fe37e72b340> (a java.util.logging.ConsoleHandler)
    at java.util.logging.ConsoleHandler.publish(ConsoleHandler.java:89)
    at java.util.logging.Logger.log(Logger.java:472)
    at java.util.logging.Logger.doLog(Logger.java:494)
    at java.util.logging.Logger.log(Logger.java:517)
    at java.util.logging.Logger.info(Logger.java:1036)
    at org.apache.solr.core.SolrCore.execute(SolrCore.java:1212)
    at org.apache.solr.servlet.SolrDispatchFilter.execute(SolrDispatchFilter.java:303)
    at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:232)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:172)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:151)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:874)
    at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:665)
    at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:528)
    at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:81)
    at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:689)
    at java.lang.Thread.run(Thread.java:619)

e esta é a última parte do meu despejo de threads:

"ContainerBackgroundProcessor[StandardEngine[Catalina]]" daemon prio=10 tid=0x00007f6510349800 nid=0xbff waiting on condition [0x0000000041d8d000..0x0000000041d8dd20]
   java.lang.Thread.State: TIMED_WAITING (sleeping)
    at java.lang.Thread.sleep(Native Method)
    at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1548)
    at java.lang.Thread.run(Thread.java:619)

"pool-1-thread-1" prio=10 tid=0x0000000000c26400 nid=0xbfe waiting on condition [0x000000004200e000..0x000000004200eca0]
   java.lang.Thread.State: WAITING (parking)
    at sun.misc.Unsafe.park(Native Method)
    - parking to wait for  <0x00007f651b275510> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
    at java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1925)
    at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:358)
    at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:946)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:906)
    at java.lang.Thread.run(Thread.java:619)

"Low Memory Detector" daemon prio=10 tid=0x00007f6510004400 nid=0xbfa runnable [0x0000000000000000..0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"CompilerThread1" daemon prio=10 tid=0x00007f6510001000 nid=0xbf9 waiting on condition [0x0000000000000000..0x0000000040d5e340]
   java.lang.Thread.State: RUNNABLE

"CompilerThread0" daemon prio=10 tid=0x00000000006bc400 nid=0xbf8 waiting on condition [0x0000000000000000..0x0000000040c5d2d0]
   java.lang.Thread.State: RUNNABLE

"Signal Dispatcher" daemon prio=10 tid=0x00000000006bb000 nid=0xbf7 runnable [0x0000000000000000..0x0000000040b5da30]
   java.lang.Thread.State: RUNNABLE

"Finalizer" daemon prio=10 tid=0x0000000000690c00 nid=0xbf6 in Object.wait() [0x000000004065e000..0x000000004065ed20]
   java.lang.Thread.State: WAITING (on object monitor)
    at java.lang.Object.wait(Native Method)
    - waiting on <0x00007f651aa10258> (a java.lang.ref.ReferenceQueue$Lock)
    at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:116)
    - locked <0x00007f651aa10258> (a java.lang.ref.ReferenceQueue$Lock)
    at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:132)
    at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:159)

"Reference Handler" daemon prio=10 tid=0x000000000068f400 nid=0xbf5 in Object.wait() [0x000000004055d000..0x000000004055dca0]
   java.lang.Thread.State: WAITING (on object monitor)
    at java.lang.Object.wait(Native Method)
    - waiting on <0x00007f651aa10338> (a java.lang.ref.Reference$Lock)
    at java.lang.Object.wait(Object.java:485)
    at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:116)
    - locked <0x00007f651aa10338> (a java.lang.ref.Reference$Lock)

"main" prio=10 tid=0x0000000000622400 nid=0xbeb runnable [0x0000000000000000..0x00007fff69fcbba0]
   java.lang.Thread.State: RUNNABLE

"VM Thread" prio=10 tid=0x000000000068a000 nid=0xbf4 runnable 

"GC task thread#0 (ParallelGC)" prio=10 tid=0x000000000062cc00 nid=0xbec runnable 

"GC task thread#1 (ParallelGC)" prio=10 tid=0x000000000062e000 nid=0xbed runnable 

"GC task thread#2 (ParallelGC)" prio=10 tid=0x000000000062f400 nid=0xbee runnable 

"GC task thread#3 (ParallelGC)" prio=10 tid=0x0000000000630400 nid=0xbef runnable 

"GC task thread#4 (ParallelGC)" prio=10 tid=0x0000000000631800 nid=0xbf0 runnable 

"GC task thread#5 (ParallelGC)" prio=10 tid=0x0000000000632c00 nid=0xbf1 runnable 

"GC task thread#6 (ParallelGC)" prio=10 tid=0x0000000000634000 nid=0xbf2 runnable 

"GC task thread#7 (ParallelGC)" prio=10 tid=0x0000000000635400 nid=0xbf3 runnable 

"VM Periodic Task Thread" prio=10 tid=0x00007f6510006800 nid=0xbfb waiting on condition 

JNI global references: 1201

Eu sei que este não é um problema de deadlock de thread, pois um thread está realmente executando com todo o recurso que todos os outros threads desejam.

Alguém tem uma idéia do que pode causar esse problema?