tomcat-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Gattu, Praveen" <>
Subject RE: Threadpool doesn't contain any threads
Date Wed, 26 Nov 2008 17:50:58 GMT
I don't think it is related to JMX. I took a stack dump and I don't see threads related to
that thread pool. To answer Kees questions, it happens randomly and there is no specific request
pattern. However whenever this happens I see a "Thread death" exception which I included in
my previous email. When I tracked it through I see that this is caused when PoolTcpEndpoint
encounters an IOException on socket accept, and it essentially either reinitializes endpoint
or if that fails, stops the endpoint(which causes to shutdown the thread pool), initializes
the endpoint and starts the endpoint.

My guess is in the "start" phase when it is trying to start the thread pool, its going into
some bad state.

There is no other activity going on, also we have a large fleet and this issue props up randomly
on some of the boxes. Since I cannot reproduce this behavior predictably I don't know if I
can say I can test it out with a prebuilt apache build.

Thanks for the comments. Any other pointers please send it my way.

-----Original Message-----
From: Filip Hanik - Dev Lists [] 
Sent: Wednesday, November 26, 2008 8:28 AM
To: Tomcat Users List
Subject: Re: Threadpool doesn't contain any threads

could just be flaky jmx code, meaning we don't publish completely 
accurate numbers


Kees Jan Koster wrote:
> Dear Praveen,
>> Everyday we are noticing the tomcat not responding on a port. On 
>> further inspection we noticed that the thread pool that is serving 
>> this port has no threads. Right around the time tomcat goes into this 
>> state, we noticed that there is a thread death, and get the following 
>> stack trace
> Does this happen randomly on the day, or at a specific time of day? Is 
> it reproducible on a test machine?
> What other activity is going on around the time that Tomcat dies? Cron 
> jobs? Backups? Network changes?
>> Did anyone else notice this issue. Another minor caveat is, we built 
>> Tomcat using JDK 1.5 but are running it on JDK 1.6. Could this be 
>> causing any issue?
> Hum. You built your own Tomcat? Is there a test environment that you 
> can test this application with a pre-built one from Just 
> to make sure.
>> Also I used Jconsole and noticed that currentThreadBusy and 
>> currentThreadCount are both -1.
> I'm not sure that these figures can be trusted once the thread pool 
> has died.
> -- 
> Kees Jan
> 06-51838192
> Human beings make life so interesting. Do you know that in a universe 
> so full of wonders,
> they have managed to invent boredom. Quite astonishing... -- Terry 
> Partchett
> ---------------------------------------------------------------------
> To start a new topic, e-mail:
> To unsubscribe, e-mail:
> For additional commands, e-mail:

To start a new topic, e-mail:
To unsubscribe, e-mail:
For additional commands, e-mail:

To start a new topic, e-mail:
To unsubscribe, e-mail:
For additional commands, e-mail:

View raw message