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Posted to notifications@accumulo.apache.org by "Josh Elser (JIRA)" <ji...@apache.org> on 2015/05/27 18:48:17 UTC

[jira] [Reopened] (ACCUMULO-3853) Contention around ConcurrentLinkedQueue.size() in AsyncSpanReceiver

     [ https://issues.apache.org/jira/browse/ACCUMULO-3853?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Josh Elser reopened ACCUMULO-3853:
----------------------------------

Asked Billie to take a look at these changes. She noted that ZooTraceClient modifies the sendQueue which I didn't realize.

> Contention around ConcurrentLinkedQueue.size() in AsyncSpanReceiver
> -------------------------------------------------------------------
>
>                 Key: ACCUMULO-3853
>                 URL: https://issues.apache.org/jira/browse/ACCUMULO-3853
>             Project: Accumulo
>          Issue Type: Bug
>          Components: trace
>    Affects Versions: 1.7.0
>            Reporter: Josh Elser
>            Assignee: Josh Elser
>             Fix For: 1.8.0, 1.7.1
>
>          Time Spent: 20m
>  Remaining Estimate: 0h
>
> Trying to debug slowness in the replication merkle test, I saw a lot of stack traces sitting here:
> {noformat}
> "replication task 1" #297 daemon prio=5 os_prio=0 tid=0x0000000004624000 nid=0x6b46 runnable [0x00007ff8867b6000]
>    java.lang.Thread.State: RUNNABLE
>         at java.util.concurrent.ConcurrentLinkedQueue.size(ConcurrentLinkedQueue.java:450)
>         at org.apache.accumulo.tracer.AsyncSpanReceiver.receiveSpan(AsyncSpanReceiver.java:171)
>         at org.apache.htrace.Tracer.deliver(Tracer.java:81)
>         at org.apache.htrace.impl.MilliSpan.stop(MilliSpan.java:177)
>         - locked <0x00000000a7fe3560> (a org.apache.htrace.impl.MilliSpan)
>         at org.apache.htrace.TraceScope.close(TraceScope.java:78)
>         at org.apache.hadoop.hdfs.DFSInputStream.read(DFSInputStream.java:898)
>         - locked <0x00000000b0086118> (a org.apache.hadoop.hdfs.DFSInputStream)
>         at java.io.DataInputStream.readFully(DataInputStream.java:195)
>         at java.io.DataInputStream.readFully(DataInputStream.java:169)
>         at org.apache.accumulo.core.data.Mutation.readFields(Mutation.java:965)
>         at org.apache.accumulo.server.data.ServerMutation.readFields(ServerMutation.java:52)
>         at org.apache.accumulo.tserver.logger.LogFileValue.readFields(LogFileValue.java:45)
>         at org.apache.accumulo.tserver.replication.AccumuloReplicaSystem.getWalEdits(AccumuloReplicaSystem.java:702)
>         at org.apache.accumulo.tserver.replication.AccumuloReplicaSystem$WalClientExecReturn.execute(AccumuloReplicaSystem.java:531)
>         at org.apache.accumulo.tserver.replication.AccumuloReplicaSystem$WalClientExecReturn.execute(AccumuloReplicaSystem.java:506)
>         at org.apache.accumulo.core.client.impl.ReplicationClient.executeServicerWithReturn(ReplicationClient.java:189)
>         at org.apache.accumulo.tserver.replication.AccumuloReplicaSystem.replicateLogs(AccumuloReplicaSystem.java:429)
>         at org.apache.accumulo.tserver.replication.AccumuloReplicaSystem._replicate(AccumuloReplicaSystem.java:291)
>         at org.apache.accumulo.tserver.replication.AccumuloReplicaSystem.replicate(AccumuloReplicaSystem.java:212)
>         at org.apache.accumulo.tserver.replication.ReplicationProcessor.process(ReplicationProcessor.java:134)
>         at org.apache.accumulo.server.zookeeper.DistributedWorkQueue$1.run(DistributedWorkQueue.java:107)
>         at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
>         at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
>         at org.apache.accumulo.fate.util.LoggingRunnable.run(LoggingRunnable.java:35)
>         at java.lang.Thread.run(Thread.java:745)
>    Locked ownable synchronizers:
>         - <0x00000000b00dbf48> (a java.util.concurrent.ThreadPoolExecutor$Worker)
> {noformat}
> Seems like this might still be related to HDFS-8069, but one odd thing is that we were sitting in the size() method.
> For those who don't remember, size() is a big o N operation on ConcurrentLinkedQueue. Calling the size() method every time we receive a new span is a little nasty.



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