On Wed, Jun 17, 2009 at 11:03 AM, Mikael
Kjerrman<mikael.kjerr...@gmail.com> wrote:
> Hi,
>
> by accident I observed that various CPU on a rather heavily loaded Oracle 
> server sometimes consumed 100% sys
> and apparently this was caused by prstat.
>
>   PID USERNAME USR SYS TRP TFL DFL LCK SLP LAT VCX ICX SCL SIG PROCESS/LWPID
> [b]  2889 root     0.0 100 0.0 0.0 0.0 0.0 0.0 0.0   0   0   0   0 
> prstat/1[/b]
>
> My question is if this is something to worry about or just works as expected?
> I would like to know because when there is problem it is very common for 
> people to start multiple prstat/top etc. to try to see what's going on and 
> that behaviour worries me more than a single instance of a prstat running.

Can you grab kernel stacks from when this happens?  Something like this:

#!/usr/sbin/dtrace -qs

profile-397
/ arg0 && execname == "prstat"/
{
        @c[stack()] = count();
}

END
{
        trunc(@c,30);
}

Run this and ctrl-C after a few seconds.  You're most likely seeing
this bug:  http://bugs.opensolaris.org/bugdatabase/view_bug.do?bug_id=6801244.
 I have a fix for this that's working its way through the system.

Chad
_______________________________________________
perf-discuss mailing list
perf-discuss@opensolaris.org

Reply via email to