Re: preempt-timing-2.6.8-rc1

Joe Korty
2004-07-13T15:08:27Z

On Tue, Jul 13, 2004 at 07:40:28AM -0700, 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?

I can scrape one up. It'll be a day or so.
Joe