Bug 60867 - Tomcat stops unexpectedly- Deadlock in thread dump
Summary: Tomcat stops unexpectedly- Deadlock in thread dump
Status: RESOLVED INVALID
Alias: None
Product: Tomcat 7
Classification: Unclassified
Component: Connectors (show other bugs)
Version: 7.0.23
Hardware: All Linux
: P2 critical (vote)
Target Milestone: ---
Assignee: Tomcat Developers Mailing List
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2017-03-15 09:52 UTC by Preeti Negi
Modified: 2017-03-16 08:41 UTC (History)
0 users



Attachments
Thread dump (454.73 KB, text/plain)
2017-03-15 09:52 UTC, Preeti Negi
Details

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Description Preeti Negi 2017-03-15 09:52:49 UTC
Created attachment 34828 [details]
Thread dump

Hi All,

Our application installed on linux server is using Apache Tomcat 7.0.23. Once in every 15 days(sometimes before) it stops unexpectedly with no exceptions. We took thread dump and found out one deadlock which could be the reason of unresponsive application.

"http-bio-8080-exec-6457" daemon prio=10 tid=0x00007fbec04fc800 nid=0x5739 waiting for monitor entry [0x00007fbea1c33000]
waiting to lock <0x00007fbeefcb53e0> (a [Ljava.util.jar.JarFile;)

Setting for connector

<Connector port="8080" protocol="HTTP/1.1"
               connectionTimeout="20000"
               redirectPort="8443" URIEncoding="UTF-8" />

Find attached thread dump.
Comment 1 Remy Maucherat 2017-03-15 10:09:42 UTC
I don't see a deadlock there, the other thread holding the lock for 0x00007fbeefcb53e0 will proceed and release it at some point.

Please investigate the performance issue on the user mailing list instead.
Comment 2 Preeti Negi 2017-03-15 10:34:57 UTC
(In reply to Remy Maucherat from comment #1)
> I don't see a deadlock there, the other thread holding the lock for
> 0x00007fbeefcb53e0 will proceed and release it at some point.
> 
> Please investigate the performance issue on the user mailing list instead.

I could see similar problems:

https://bz.apache.org/bugzilla/show_bug.cgi?id=57779

https://bz.apache.org/bugzilla/show_bug.cgi?id=53173

And the thread is in blocked state.
Comment 3 Mark Thomas 2017-03-15 12:41:51 UTC
(In reply to Preeti Negi from comment #2)
> (In reply to Remy Maucherat from comment #1)
> > I don't see a deadlock there, the other thread holding the lock for
> > 0x00007fbeefcb53e0 will proceed and release it at some point.
> > 
> > Please investigate the performance issue on the user mailing list instead.

Indeed. There is no bug here.

> I could see similar problems:

Those are not similar. Help with how to read thread dumps is available via the users list.

<snip/>

> And the thread is in blocked state.

BLOCKED != deadlock

This belongs on the users mailing list.
Comment 4 Preeti Negi 2017-03-16 03:43:02 UTC
(In reply to Mark Thomas from comment #3)
> (In reply to Preeti Negi from comment #2)
> > (In reply to Remy Maucherat from comment #1)
> > > I don't see a deadlock there, the other thread holding the lock for
> > > 0x00007fbeefcb53e0 will proceed and release it at some point.
> > > 
> > > Please investigate the performance issue on the user mailing list instead.
> 
> Indeed. There is no bug here.
> 
> > I could see similar problems:
> 
> Those are not similar. Help with how to read thread dumps is available via
> the users list.
> 
> <snip/>
> 
> > And the thread is in blocked state.
> 
> BLOCKED != deadlock
> 
> This belongs on the users mailing list.

Yes my mistake I wrote Deadlock instead of BLOCKED.

But from online dump analyzer, it says, it could be a reason of unresponsive application.

I am new here. Kindly tell me what is users mailing list ?
Comment 5 mgrigorov 2017-03-16 08:41:53 UTC
Please read http://tomcat.apache.org/lists.html#tomcat-users.
The users mailing list is the place where to ask how to use Tomcat, how to configure it, etc. You can also answer someone else's questions if you know the answer.
Bugzilla is used for bug reports and enhancement requests.
It is always better to discuss the bug/enhancement in the mailing lists first.