lkml.org 
[lkml]   [2004]   [Jul]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: preempt-timing-2.6.8-rc1
William Lee Irwin III wrote:
> On Tue, Jul 13, 2004 at 05:28:05AM -0700, William Lee Irwin III wrote:
>
>>>This patch uses the preemption counter increments and decrements to time
>>>non-preemptible critical sections.
>>>This is an instrumentation patch intended to help determine the causes of
>>>scheduling latency related to long non-preemptible critical sections.
>>>Changes from 2.6.7-based patch:
>>>(1) fix unmap_vmas() check correctly this time
>>>(2) add touch_preempt_timing() to cond_resched_lock()
>>>(3) depend on preempt until it's worked out wtf goes wrong without it
>
>
> On Tue, Jul 13, 2004 at 10:36:00AM -0400, Joe Korty wrote:
>
>>You preemption-block hold times will improve *enormously* if you move all
>>softirq processing down to the daemon (and possibly raise the daemon to
>>one of the higher SCHED_RR priorities, to compensate for softirq processing
>>no longer happening at interrupt level).
>
>
> Plausible. Got a patch?
>

Make MAX_SOFTIRQ_RESTART 1?

I don't think you should make ksoftirq a realtime task, because that
defeats the purpose of having it to prevent livelocking userspace
doesn't it?

However, you may want to increase it from nice +19. Probably just to
nice 0 would be an idea.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 14:04    [from the cache]
©2003-2014 Jasper Spaans. Advertise on this site