[ 
https://issues.apache.org/jira/browse/SSHD-348?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14270925#comment-14270925
 ] 

Saša Živkov commented on SSHD-348:
----------------------------------

Unfortunately, on our productive Gerrit, where we use the 0.9.0 version or more 
precisely the 0.9.x branch of mina-sshd,
the same issue occurred today. All threads blocked in the waitForSpace method.

The 0.9.0 version was long believed to be free of this issue. It doesn't seem 
to be true... maybe the issue is just less
likely to happen on 0.9.0 than on a newer version.

> Some SSH threads get blocked in Object.wait() method forever
> ------------------------------------------------------------
>
>                 Key: SSHD-348
>                 URL: https://issues.apache.org/jira/browse/SSHD-348
>             Project: MINA SSHD
>          Issue Type: Bug
>    Affects Versions: 0.10.0, 0.10.1, 0.11.0, 0.12.0, 0.13.0
>         Environment: Gerrit Code Review 2.9.1 (SSHD 0.12.0)
> Gerrit Code Review 2.9.2 (SSHD 0.13.0)
> Gerrit Code Review 2.9.3 (Downgraded to SSHD 0.9)
>            Reporter: David Ostrovsky
>            Assignee: Guillaume Nodet
>            Priority: Blocker
>             Fix For: 0.14.0
>
>         Attachments: 0001-Prepare-release-sshd-0.13.0-72f868e26.patch, diff
>
>
> This seems to be a regression started from 0.10.1.
> In Gerrit we have SSH commamds that returns immediately and so called 
> stream-events command which keeps connection open until clients disconnect. 
> Basically for days or weeks. This is used for example to inform CI system 
> (jenkins) about events in gerrit, like new patch set upload etc.
> In Gerrit we have configurable "SSH-Stream-Worker" thread pool which is 
> dedicated to the mentioned stream-events SSH command. The observed behaviour 
> on latest SSHD release is that after some time all threads are stuck. They 
> aren't stuck at the same time, but one after another untill at some time all 
> threads are stuck and Gerrit must be restarted. Usually after one week. The 
> stack dump of all such stuck thread are the same, see below. If we had a 
> patch we could apply it to our production Gerrit instance and try if this 
> helps.
> {code}
> "SSH-Stream-Worker-10" cpu=95400.00 [reset 95400.00] ms elapsed=146444.30 
> [reset 146444.30] s allocated=5526700000 B (5.15 GB) [reset 5526700000 B 
> (5.15 GB)] defined_classes=0
> io= file i/o: 15622752/0 B, net i/o: 0/0 B, files opened:0, socks opened:0  
> [reset file i/o: 15622752/0 B, net i/o: 0/0 B, files opened:0, socks opened:0 
> ] 
> prio=10 tid=0x00007f54514df800 nid=0x1c71 / 7281  pthread-id=139999281374976 
> in Object.wait()  [_thread_blocked (_at_safepoint), 
> stack(0x00007f541f5f6000,0x00007f541f6f7000)] [0x00007f541f6f5000]
>    java.lang.Thread.State: WAITING (on object monitor)
>       at java.lang.Object.wait(J)V(Native Method)
>       - waiting on <0x00007f553aa530d0> (a 
> org.apache.sshd.common.channel.Window)
>       at java.lang.Object.wait()V(Object.java:503)
>       at 
> org.apache.sshd.common.channel.Window.waitForSpace()I(Window.java:148)
>       - locked <0x00007f553aa530d0> (a org.apache.sshd.common.channel.Window)
>       at 
> org.apache.sshd.common.channel.ChannelOutputStream.flush()V(ChannelOutputStream.java:116)
>       - locked <0x00007f553aa55060> (a 
> org.apache.sshd.common.channel.ChannelOutputStream)
>       at 
> org.apache.sshd.common.channel.ChannelOutputStream.write([BII)V(ChannelOutputStream.java:84)
>       - locked <0x00007f553aa55060> (a 
> org.apache.sshd.common.channel.ChannelOutputStream)
>       at sun.nio.cs.StreamEncoder.writeBytes()V(StreamEncoder.java:221)
>       at sun.nio.cs.StreamEncoder.implFlushBuffer()V(StreamEncoder.java:291)
>       at sun.nio.cs.StreamEncoder.implFlush()V(StreamEncoder.java:295)
>       at sun.nio.cs.StreamEncoder.flush()V(StreamEncoder.java:141)
>       - locked <0x00007f553aa7e258> (a java.io.OutputStreamWriter)
>       at java.io.OutputStreamWriter.flush()V(OutputStreamWriter.java:229)
>       at java.io.BufferedWriter.flush()V(BufferedWriter.java:254)
>       - locked <0x00007f553aa7e258> (a java.io.OutputStreamWriter)
>       at java.io.PrintWriter.flush()V(PrintWriter.java:320)
>       - locked <0x00007f553aa7e210> (a java.io.BufferedWriter)
>       at java.io.PrintWriter.checkError()Z(PrintWriter.java:357)
>       at 
> com.google.gerrit.sshd.commands.StreamEvents.writeEvents()V(StreamEvents.java:186)
>       at 
> com.google.gerrit.sshd.commands.StreamEvents.access$100(Lcom/google/gerrit/sshd/commands/StreamEvents;)V(StreamEvents.java:43)
>       at 
> com.google.gerrit.sshd.commands.StreamEvents$3.run()V(StreamEvents.java:82)
>       at 
> java.util.concurrent.Executors$RunnableAdapter.call()Ljava/lang/Object;(Executors.java:471)
>       at java.util.concurrent.FutureTask.run()V(FutureTask.java:262)
>       at 
> java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(Ljava/util/concurrent/ScheduledThreadPoolExecutor$ScheduledFutureTask;)V(ScheduledThreadPoolExecutor.java:178)
>       at 
> java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run()V(ScheduledThreadPoolExecutor.java:292)
>       at 
> com.google.gerrit.server.git.WorkQueue$Task.run()V(WorkQueue.java:364)
>       at 
> java.util.concurrent.ThreadPoolExecutor.runWorker(Ljava/util/concurrent/ThreadPoolExecutor$Worker;)V(ThreadPoolExecutor.java:1145)
>       at 
> java.util.concurrent.ThreadPoolExecutor$Worker.run()V(ThreadPoolExecutor.java:615)
>       at java.lang.Thread.run()V(Thread.java:812)
> {code}



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to