> Our local test environment mini cluster goes nuts right after start up. It is a two node/shard/replica collection starts up normally if only one node start up.  But as soon as the second node attempts to join the cluster, both nodes go crazy, creating thousands of threads with identical stack traces.
>
> "qtp1458849419-4738" - Thread t@4738
>    java.lang.Thread.State: TIMED_WAITING
>         at sun.misc.Unsafe.park(Native Method)
>         - parking to wait for <6ee32168> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
>         at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
>         at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2078)
>         at org.eclipse.jetty.util.BlockingArrayQueue.poll(BlockingArrayQueue.java:392)
>         at org.eclipse.jetty.util.thread.QueuedThreadPool.idleJobPoll(QueuedThreadPool.java:600)
>         at org.eclipse.jetty.util.thread.QueuedThreadPool.access$800(QueuedThreadPool.java:49)
>         at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:663)
>         at java.lang.Thread.run(Thread.java:748)
>
>    Locked ownable synchronizers:
>         - None
>
> If does not happen always, but most of the time i am unable to boot the cluster normally. Sometimes, apparently right now for the first time, the GUI is still accessible.
>
> Is this a known issue?

> From:Shawn Heisey <[EMAIL PROTECTED]>
> Sent: Friday 8th June 2018 16:47
> To: [EMAIL PROTECTED]
> Subject: Re: 7.3.1 creates thousands of threads after start up
>
> On 6/8/2018 8:17 AM, Markus Jelsma wrote:
> > Our local test environment mini cluster goes nuts right after start up. It is a two node/shard/replica collection starts up normally if only one node start up.  But as soon as the second node attempts to join the cluster, both nodes go crazy, creating thousands of threads with identical stack traces.
> >
> > "qtp1458849419-4738" - Thread t@4738
> >    java.lang.Thread.State: TIMED_WAITING
> >         at sun.misc.Unsafe.park(Native Method)
> >         - parking to wait for <6ee32168> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
> >         at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
> >         at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2078)
> >         at org.eclipse.jetty.util.BlockingArrayQueue.poll(BlockingArrayQueue.java:392)
> >         at org.eclipse.jetty.util.thread.QueuedThreadPool.idleJobPoll(QueuedThreadPool.java:600)
> >         at org.eclipse.jetty.util.thread.QueuedThreadPool.access$800(QueuedThreadPool.java:49)
> >         at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:663)
> >         at java.lang.Thread.run(Thread.java:748)
> >
> >    Locked ownable synchronizers:
> >         - None
> >
> > If does not happen always, but most of the time i am unable to boot the cluster normally. Sometimes, apparently right now for the first time, the GUI is still accessible.
> >
> > Is this a known issue?
>
> It's not a problem that I've heard of.  There are no Solr classes in the
> stacktrace, only Jetty and Java classes.  I won't try to tell you that a
> bug in Solr can't be the root cause, because it definitely can.  The
> threads appear to be created by Jetty, but the supplied info doesn't
> indicate WHY it's happening.
>
> Presumably there's a previous version you've used where this problem did
> NOT happen.  What version would that be?
>
> Can you share the solr.log file from both nodes when this happens? 
> There might be a clue there.
>
> It sounds like you probably have a small number of collections in the

> Hello Shawn,
>
> The logs appear useless, they are littered with these:
>
> 2018-06-08 14:02:47.382 ERROR (qtp1458849419-1263) [   ]
> o.a.s.s.HttpSolrCall null:org.apache.solr.common.SolrException: Error
> trying to proxy request for url: http://idx2:8983/solr/
> search/admin/ping <http://idx2:8983/solr/search/admin/ping>
>         at
> org.apache.solr.servlet.HttpSolrCall.remoteQuery(HttpSolrCall.java:647)
>         at org.apache.solr.servlet.HttpSolrCall.call(HttpSolrCall.java:501)
>         at
> org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:384)
> ..
>         at
> org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:131)
>         at
> org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:382)
>         at
> org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:708)
>         at
> org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:626)
>         at java.lang.Thread.run(Thread.java:748)
> Caused by: org.eclipse.jetty.io.EofException
>         at
> org.eclipse.jetty.server.HttpConnection$SendCallback.reset(HttpConnection.java:704)
> ..
>         at org.eclipse.jetty.server.HttpOutput.write(HttpOutput.java:509)
>
> Regarding the versions, it is a bit hard to recall but i do no thing i
> have seen this on 7.2, most certainly not on 7.1.
>
> We operate three distinct type of Solr collections, they only share the
> same Zookeeper quorum. The other two collections do not seem to have this
> problem, but i don't restart those as often as i restart this collection,
> as i am STILL trying to REPRODUCE the dreaded memory leak i reported having
> on 7.3 about two weeks ago. Sorry, but i drives me nuts!
>
> Thanks,
> Markus
>
> -----Original message-----
> > From:Shawn Heisey <[EMAIL PROTECTED]>
> > Sent: Friday 8th June 2018 16:47
> > To: [EMAIL PROTECTED]
> > Subject: Re: 7.3.1 creates thousands of threads after start up
> >
> > On 6/8/2018 8:17 AM, Markus Jelsma wrote:
> > > Our local test environment mini cluster goes nuts right after start
> up. It is a two node/shard/replica collection starts up normally if only
> one node start up.  But as soon as the second node attempts to join the
> cluster, both nodes go crazy, creating thousands of threads with identical
> stack traces.
> > >
> > > "qtp1458849419-4738" - Thread t@4738
> > >    java.lang.Thread.State: TIMED_WAITING
> > >         at sun.misc.Unsafe.park(Native Method)
> > >         - parking to wait for <6ee32168> (a
> java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
> > >         at
> java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
> > >         at
> java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2078)
> > >         at
> org.eclipse.jetty.util.BlockingArrayQueue.poll(BlockingArrayQueue.java:392)
> > >         at
> org.eclipse.jetty.util.thread.QueuedThreadPool.idleJobPoll(QueuedThreadPool.java:600)
> > >         at
> org.eclipse.jetty.util.thread.QueuedThreadPool.access$800(QueuedThreadPool.java:49)
> > >         at
> org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:663)
> > >         at java.lang.Thread.run(Thread.java:748)
> > >
> > >    Locked ownable synchronizers:
> > >         - None
> > >
> > > If does not happen always, but most of the time i am unable to boot
> the cluster normally. Sometimes, apparently right now for the first time,
> the GUI is still accessible.
> > >
> > > Is this a known issue?
> >
> > It's not a problem that I've heard of.  There are no Solr classes in the
> > stacktrace, only Jetty and Java classes.  I won't try to tell you that a
> > bug in Solr can't be the root cause, because it definitely can.  The
> > threads appear to be created by Jetty, but the supplied info doesn't

> From:Deepak Goel <[EMAIL PROTECTED]>
> Sent: Friday 8th June 2018 17:14
> To: [EMAIL PROTECTED]
> Subject: Re: 7.3.1 creates thousands of threads after start up
>
> Do these machines have a firewall in-between?
>
> On Fri, 8 Jun 2018, 20:29 Markus Jelsma, <[EMAIL PROTECTED]> wrote:
>
> > Hello Shawn,
> >
> > The logs appear useless, they are littered with these:
> >
> > 2018-06-08 14:02:47.382 ERROR (qtp1458849419-1263) [   ]
> > o.a.s.s.HttpSolrCall null:org.apache.solr.common.SolrException: Error
> > trying to proxy request for url: http://idx2:8983/solr/
> > search/admin/ping <http://idx2:8983/solr/search/admin/ping>
> >         at
> > org.apache.solr.servlet.HttpSolrCall.remoteQuery(HttpSolrCall.java:647)
> >         at org.apache.solr.servlet.HttpSolrCall.call(HttpSolrCall.java:501)
> >         at
> > org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:384)
> > ..
> >         at
> > org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:131)
> >         at
> > org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:382)
> >         at
> > org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:708)
> >         at
> > org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:626)
> >         at java.lang.Thread.run(Thread.java:748)
> > Caused by: org.eclipse.jetty.io.EofException
> >         at
> > org.eclipse.jetty.server.HttpConnection$SendCallback.reset(HttpConnection.java:704)
> > ..
> >         at org.eclipse.jetty.server.HttpOutput.write(HttpOutput.java:509)
> >
> > Regarding the versions, it is a bit hard to recall but i do no thing i
> > have seen this on 7.2, most certainly not on 7.1.
> >
> > We operate three distinct type of Solr collections, they only share the
> > same Zookeeper quorum. The other two collections do not seem to have this
> > problem, but i don't restart those as often as i restart this collection,
> > as i am STILL trying to REPRODUCE the dreaded memory leak i reported having
> > on 7.3 about two weeks ago. Sorry, but i drives me nuts!
> >
> > Thanks,
> > Markus
> >
> > -----Original message-----
> > > From:Shawn Heisey <[EMAIL PROTECTED]>
> > > Sent: Friday 8th June 2018 16:47
> > > To: [EMAIL PROTECTED]
> > > Subject: Re: 7.3.1 creates thousands of threads after start up
> > >
> > > On 6/8/2018 8:17 AM, Markus Jelsma wrote:
> > > > Our local test environment mini cluster goes nuts right after start
> > up. It is a two node/shard/replica collection starts up normally if only
> > one node start up.  But as soon as the second node attempts to join the
> > cluster, both nodes go crazy, creating thousands of threads with identical
> > stack traces.
> > > >
> > > > "qtp1458849419-4738" - Thread t@4738
> > > >    java.lang.Thread.State: TIMED_WAITING
> > > >         at sun.misc.Unsafe.park(Native Method)
> > > >         - parking to wait for <6ee32168> (a
> > java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
> > > >         at
> > java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
> > > >         at
> > java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2078)
> > > >         at
> > org.eclipse.jetty.util.BlockingArrayQueue.poll(BlockingArrayQueue.java:392)
> > > >         at
> > org.eclipse.jetty.util.thread.QueuedThreadPool.idleJobPoll(QueuedThreadPool.java:600)
> > > >         at
> > org.eclipse.jetty.util.thread.QueuedThreadPool.access$800(QueuedThreadPool.java:49)
> > > >         at
> > org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:663)
> > > >         at java.lang.Thread.run(Thread.java:748)
> > > >
> > > >    Locked ownable synchronizers:
> > > >         - None
> > > >
> > > > If does not happen always, but most of the time i am unable to boot

> 2018-06-08 14:02:47.382 ERROR (qtp1458849419-1263) [   ] o.a.s.s.HttpSolrCall null:org.apache.solr.common.SolrException: Error trying to proxy request for url: http://idx2:8983/solr/
> search/admin/ping

> From:Shawn Heisey <[EMAIL PROTECTED]>
> Sent: Sunday 10th June 2018 22:42
> To: [EMAIL PROTECTED]
> Subject: Re: 7.3.1 creates thousands of threads after start up
>
> On 6/8/2018 8:59 AM, Markus Jelsma wrote:
> > 2018-06-08 14:02:47.382 ERROR (qtp1458849419-1263) [   ] o.a.s.s.HttpSolrCall null:org.apache.solr.common.SolrException: Error trying to proxy request for url: http://idx2:8983/solr/
> > search/admin/ping
> <snip>
> > Caused by: org.eclipse.jetty.io.EofException
>
> If you haven't tweaked the shard handler config to drastically reduce
> the socket timeout, that is weird.  The only thing that comes to mind is
> extreme GC pauses that cause the socket timeout to be exceeded.
>
> > We operate three distinct type of Solr collections, they only share the same Zookeeper quorum. The other two collections do not seem to have this problem, but i don't restart those as often as i restart this collection, as i am STILL trying to REPRODUCE the dreaded memory leak i reported having on 7.3 about two weeks ago. Sorry, but i drives me nuts!
>
> I've reviewed the list messages about the leak.  As you might imagine,
> my immediate thought is that the custom plugins you're running are
> probably the cause, because we are not getting OOME reports like I would
> expect if there were a leak in Solr itself.  It would not be unheard of
> for a custom plugin to experience no leaks with one Solr version but
> leak when Solr is upgraded, requiring a change in the plugin to properly
> close resources.  I do not know if that's what's happening.
>
> A leak could lead to GC pause problems, but it does seem really odd for
> that to happen on a Solr node that's just been started.  You could try
> bumping the heap size by 25 to 50 percent and see if the behavior
> changes at all.  Honestly I don't expect it to change, and if it
> doesn't, then I do not know what the next troubleshooting step should
> be.  I could review your solr.log, though I can't be sure I would see
> something you didn't.
>
> Thanks,
> Shawn
>
>