Intermittent system hangs on 7.2-RELEASE-p1
John Baldwin
jhb at freebsd.org
Wed Aug 26 20:43:54 UTC 2009
On Wednesday 26 August 2009 3:03:13 pm Linda Messerschmidt wrote:
> I'm trying to troubleshoot an intermittent Apache performance problem,
> and I've narrowed it down using to what appears to be a brief
> whole-system hang that last from 0.5 - 3 seconds. They occur every
> few minutes.
One thing to note is that ktrace only logs voluntary context switches (i.e.
call to tsleep or waiting on a condition variable). It specifically does not
log preemptions or blocking on a mutex, so in theory if your machine was
livelocked temporarily that might explain this.
--
John Baldwin
More information about the freebsd-hackers
mailing list