Native preemption is the culprit [was Re: today's CURRENT lockups]

[Martin Blapp]

Hi,

> I'm seeing the same effect here on a 2 CPU IBM server running without HTT. The
> server is completly locked. We have running mimedefang on it and clamd, after
> 2-3 hours running, suddenly the processlist grows and grows and the box is not
> accessibe anymore.
>
> > By disabling the "#define PREEMPTION" entry in param.h with SCHED_4BSD,
> > I'm able to complete the benchmark several times in a row without apparent
> > problems. However, I'll leave it running for a few more hours and see if I
> > didn't just "get lucky".  I'll then try SCHED_ULE w/o PREEMPTION.

Tried that. PREEMPTION seems to to be the culprit. It must be something else.
I just got another lock with "#define PREEMPTION" removed !

Martin