Re: dynamic sched timeslices

Christoph Hellwig
2004-03-15T23:01:24Z

On Mon, Mar 15, 2004 at 11:42:01PM +0100, Kurt Garloff wrote:
> Hi,
>
> attached patch allows userspace to tune the scheduling timeslices.
> It can be used for a couple of things:
> * Tune a workload for batch processing:
> You'd probably wnat to use long timeslices in order to not reschedule
> as often to make good use of your CPU caches
> * Tune a workload for interactive use:
> Under load, you may want to reduce the scedulilng latencies by using
> shorter timeslices (and there are situations where the interactiviy
> tweak -- even if they were perfect -- can't save you).
> * Tune the ration betweeen maximum and minimum timeslices to make
> nice much nicer e.g.
>
> The patch exports /proc/sys/kernel/max_timeslice and min_timeslice,
> unites are us. It also exports HZ (readonly).
> The patch implementes the desktop boot parameter which introduces
> shorter timeslices.
>
> Patch is from andrea and is in our 2.4 tree; 2.6 port was done by me and
> straightforward.

Remove the silly desktop boot parameter and the patch looks basically
okay to me.

I remember we had a more complete patch to allow tuning the scheduler
through sysctls in -mm once, though. Questions is why that one wasn't
merged and if the same reasons apply to a 'light' version.