openjpa-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Ravi P Palacherla (JIRA)" <>
Subject [jira] [Commented] (OPENJPA-1970) CPU spinning forever at TreeMap.get in
Date Thu, 31 Mar 2011 20:57:09 GMT


Ravi P Palacherla commented on OPENJPA-1970:


The only issue in including the test case is there is a chance of OutOfMemory.
The test case uses 10 threads out of which 6 threads continuously add elements (1million)
to TreeMap and 4 threads tries to retrieve the added elements.
So there is a chance that the test can run into OutOfMemory.

Even with the above setup Iam able to replicate the issue only on a dual core machine and
if the issue is reproduced 1 out of 10 runs.
I have a wrapper shell script that runs the same test 10 times and I always see that one of
these tests hang (CPU spin) at TreeMap.get.

Regarding running this test case on trunk, I did not encounter the issue on trunk (using same
wrapped shell script), 
can not say that the issue does not exist in trunk but I did not see it happen while running
the same test case in trunk.


> CPU spinning forever at TreeMap.get in 
> ---------------------------------------------------
>                 Key: OPENJPA-1970
>                 URL:
>             Project: OpenJPA
>          Issue Type: Bug
>          Components: jdbc
>    Affects Versions: 1.1.1
>         Environment: openJPA 1.1.x
>            Reporter: Ravi P Palacherla
>            Assignee: Ravi P Palacherla
>             Fix For: 1.1.1
>         Attachments: OPENJPA-1970.diff
> CPU is spinning forever at TreeMap.get in
> The reason found to be because of structural modification of treemap outside a synchronized
> Synchronizing the treemap is fixing the issue.
> The issue can be reproduced with an openJPA test case but due to the nature of the problem,
it is replicable intermittently on dual core machine.
> Attached patch has the test case and also the test case is ignored in default runs because
it will cause the tests to stuck at TreeMap.get.
> This is seen in 1.1.x version of openJPA and hence uploading the patch only for that

This message is automatically generated by JIRA.
For more information on JIRA, see:

View raw message