[patch] preempt-timing-on-2.6.8-rc2-O2

Ingo Molnar
2004-08-02T10:07:27Z

* Ingo Molnar <mingo@elte.hu> wrote:

> i've uploaded the preempt-timing patch (relative to -O2):
>
> http://redhat.com/~mingo/voluntary-preempt/preempt-timing-on-2.6.8-rc2-O2
>
> QuickStart for those who havent used it yet: enable PREEMPT_TIMING in
> .config and add preempt_thresh=1000 [== 1000 usec threshold] to the
> kernel's boot options.
>
> i changed the original patch to make it a bit more usable - the
> threshold can be changed runtime via /proc/sys/kernel/preempt_thresh,
> and the units are microseconds not milliseconds.

i've uploaded a new version of the patch, this solves a problem when
using a smaller than 1000 usecs threshold: idle time got accounted as
delay too which flooded the log. The new patch makes idle=poll the
default and that function calls touch_preempt_timing().

Ingo