Re: [PATCH] BUG(): sched.c: Line 944

Steven Cole
2002-09-17T20:57:04Z

On Tue, 2002-09-17 at 14:06, Robert Love wrote:
> On Tue, 2002-09-17 at 15:54, Steven Cole wrote:
>
> Thank you for the testing, Steven.
>
> > Running dbench 3 resulted in the dbench clients hanging and being
> > unkillable with kill -9 in the D state.
>
> Hrm, I cannot reproduce this. I just successfully completed a `dbench
> 16'. Can you find where they are hanging? You can get a trace via
> sysrq. You can also see where they are in the kernel via the wchan
> field of ps: "ps -ewo user,pid,priority,%cpu,stat,command,wchan" is a
> favorite of mine.
Sorry, it hung so badly that it didn't respond to that.
>
> Sure it does not happen with a stock kernel (no preempt)?

I just began testing plain vanilla 2.5.35-bk3 without preempt, and the
box has run up to 24 clients so far. So far so good.

>
> What if you replace the printk() and dump_stack() in schedule() with a
> no-op (but not something that will optimize away the conditional, i.e.
> try a cpu_relax()).

I'll try that in a bit.

Steven