tomcat-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Boris Prochazka <bo...@ipunplugged.com>
Subject Hanging threads on JIoEndpoint$Worker.await() in TC-6.0.13 JRE-1.6.0u1
Date Wed, 11 Jul 2007 11:24:15 GMT
To start with I am not sure this is the right place for posting this
problem/behaviur and I am not claiming nither that it is a bug, just
something that may bee fragile in Tomcat-6.

What I have noticed is that after a couple of hours traffic I get a large
number (20 or more) of threads that are hanging on JIoEndpoint$Worker.await()

With Jconsole I get the following stack trace:

 Name: http-8443-14
 State: WAITING on org.apache.tomcat.util.net.JIoEndpoint$Worker@239744
 Total blocked: 0  Total waited: 1

 Stack trace:
 java.lang.Object.wait(Native Method)
 java.lang.Object.wait(Object.java:485)
 org.apache.tomcat.util.net.JIoEndpoint$Worker.await(JIoEndpoint.java:416)
 org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:442)
 java.lang.Thread.run(Thread.java:619)

I don't know what's the origin for this. There are no special messages
in the logs and I can't see any stackdumps from exception during the
time when the threads were created. The major traffic during the time has
been requesting the same jsp page (pings for validating that the TC is up)
that involves very little application code.

I suspect that number of worker threads are limited and if this keeps on
increasing this will finally crash the TC. It may be a good approach
to set a time limit on the worker threads and thereby get it self
healing or this may be a TC bug that of course is best if it's fixed.

OpenSUSE-10.2, kernel 2.6.18.8-0.3-default #1 SMP
TC-6.0.13
JDK 1.6.0 u1

/Boris

.....................................................................
Boris Prochazka                 E-mail: boris@ipunplugged.com
Arenavagen 23, Box 101 60       http://www.ipunplugged.com
SE-121 28 Stockholm Globen      [home]   +46  8  - 6040786
                                [office] +46  8  - 7255919
SWEDEN                          [mobile] +46 70  - 5125122

---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@tomcat.apache.org
For additional commands, e-mail: dev-help@tomcat.apache.org


Mime
View raw message