Thanks Igor / Martijn for your help.

As you mentioned Wicket had nothing to do with it.  I had a piece of code
that was executed when a user clicked a certain link and was blocking by
accident, caught in a loop peging the CPU.  Your suggestions of kill -3 to
get the thread dump over a couple of samples helped me to narrow down the
issue and fix it.

Thanks very much.

Jeremy

On Tue, Mar 18, 2008 at 4:26 PM, Martijn Dashorst <
[EMAIL PROTECTED]> wrote:

> I suggest getting a thread dump at the time of the exception, to see
> which threads are stuck. You can do that by sending a kill -3 to the
> java process running your webapp. The stack traces should be in your
> console output captured by your server.
>
> Martijn
>
> On 3/18/08, Igor Vaynberg <[EMAIL PROTECTED]> wrote:
> > i think the only way this can happen is that you have something that
> >  really takes longer then 1 minute to execute. i dont see how wicket
> >  can take over your cpu....so may be it is that runaway process that
> >  does that...
> >
> >  i think to debug it you might want to attach a profiler to the server
> >  and wait for it to happen, take a cpu timing profile and see what was
> >  going on during the spike...
> >
> >  does the message tell you who it is locked by? which page or
> >  otherwise? if not that is possibly something we can improve also...
> >
> >  -igor
> >
> >
> >  On Tue, Mar 18, 2008 at 1:06 PM, Jeremy Levy <[EMAIL PROTECTED]> wrote:
> >  > I am seeing the "After 1 minute the Pagemap null is still locked"
> error in
> >  >  production a couple of times a day for about the last week or so.
>  We put in
> >  >  a major update to our site about 3 weeks ago, but only recently
> started
> >  >  seeing this error.  I suspect they are related.
> >  >
> >  >  From doing some research on the mailinglist it seems that this comes
> up when
> >  >  a user requests a new page while there is an open request still
> processing.
> >  >
> >  >  http://www.nabble.com/pagemap-locking-to11350774.html#a11350774
> >  >
> >  >  At the same time (or a few seconds before) the CPU is pegged at 100%
> and
> >  >  stays that way.  Overtime the CPU usage progressively gets more and
> more
> >  >  backed up (I assume because this issue keeps happening and compounds
> the
> >  >  load).
> >  >
> >  >  The longest page request on the site is a panel which has 4 child
> lazy
> >  >  loading panels but none of them take longer then a max of 4 seconds,
> which
> >  >  is pretty strictly enforced.
> >  >
> >  >  The CPU getting pegged is a huge problem because it is forcing us to
> restart
> >  >  the server every some often.
> >  >
> >  >  For now we have not been able to reproduce this error in a
> development
> >  >  environment, any suggestions, or troubleshooting ideas?
> >  >
> >  >  Jeremy
> >  >
> >
> >
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