Apache Tomcat crash on 6.1

[Martijn Veening]

Hi Kurt, thanx,
see below, for remarks:

On Thu, 2006-07-06 at 15:14, Kurt Miller wrote:

> Hi Martijn,
> 
> On Wednesday 05 July 2006 5:28 pm, Martijn Veening wrote:
> > Hi Kurt, thnx for suggestions,
> > 
> > Indeed it seems that java process memory increases, although the reading
> > is different from the tomcat manager reading. The size started at 450M
> > (res 100M) and after 6 hours increased to 600M (res 160M). I can imagine
> > that if that continues another 10 hours, the 1 Gb limit is reached
> > causing crash.
> > Tomcat however read lower memory-usage, but that will be memory within
> > the JVM-reserved memory, which differs from the process-memory in
> > FreeBSD (I presume).
> 
> Right, tomcat reported memory usage doesn't account for
> memory the jvm uses in addition to the java object heap.
> 
> Hmmm, looking over the original bug report I don't see
> -Xmx or -Xms arguments being used. Also, it could take
> some time for the java process memory utilization to
> stabilize. Even after it stabilizes there is some
> fluctuation when full GC's occur.
> 
> For the sake of minimizing some of these issues, try
> running tomcat with -Xmx250m -Xms250m so that all of
> the java heap is allocated upfront and then look for
> increasing java process memory usage after things
> stabilize.

>From the beginning it runs with Xms200m and Xmx256m opts (added in
catalina.sh script).
It now runs for 16 hours and has added up to SIZE=891m and RES=581m
(says 'top').
It increases slowaly, but continually.
I run tomcat as root at the moment, which is unadvisory ofcourse, but
will change that to specific tomcat-user soon. Perhaps that's a key ?

> > 
> > Could it be a memory leak ? Or is this increase normal because it
> > contains cached memory which can be freed when nescessary ?
> 
> I'm not sure yet if you've found a leak or not.

Not in our app no, it runs on Linux and Windows flawlessly without any
problems/mem issues.

> 
> > And where could I see the diagnostic message for the malloc() function ?
> 
> The man page for malloc() says it goes to stderr.
> 
> Regards,
> -Kurt
>