Re: O(1) scheduler observations

[Ingo Molnar]

On Fri, 1 Feb 2002, Alastair Stevens wrote:

> Just a brief observation on the O(1) scheduler. I'm using 2.4.18-pre7
> + J7 scheduler patch (haven't had a chance to try J9 yet), on a
> bog-standard Celeron 500MHz / 384Mb / IDE desktop machine under Red
> Hat 7.2.
>
> I'm blasting along in Tuxracer (discovery of the week!) and then
> "updatedb" kicks in. Tuxracer crawls and jerks for about 15 seconds,
> and then turns wonderfully smooth again, whilst the drive continues to
> thrash a while longer.

well, CPU hogs such as Tuxracer are not as highprio as they used to be.
updatedb has a mixed CPU-intensive and IO-intensive scheduling pattern,
which gives it priority over that of Tuxracer.

One solution would be to start Tuxracer at nice -10, or to renice updatedb
to nice +19.

	Ingo