Re: [CFT][PATCH] new scheduler policy

[Nick Piggin]

Roger Luethi wrote:

> On Fri, 22 Aug 2003 23:08:40 +1000, Nick Piggin wrote:
>
> > > I timed a pathological benchmark from hell I've been playing with lately.
> > > Three consecutive runs following a fresh boot. Time is in seconds:
> > >
> > > 2.4.21			821	21	25
> > > 2.6.0-test3-mm1		724	946	896
> > > 2.6.0-test3-mm1-nick	905	987	997
> > >
> > > Runtime with ideal scheduling: < 2 seconds (we're thrashing).
> > Cool. Can you post the benchmark source please?
>
> http://hellgate.ch/code/ploc/thrash.c
>
> A parallel kernel build can generate some decent thrashing, too, but I
> wanted a short and simple test case that conveniently provides the
> information I need for both logging daemon and post processing tool.
>
> Note: The benchmark could trivially be made more evil which would prevent
> 2.4.21 from finishing over 30 times faster (as it often does). I
> intentionally left it they way it is.
>
> While everybody seems to be working on interactivity, I am currently
> looking at this corner case. This should be pretty much orthogonal to your
> own work.

Yes, improvements for this problem are usually in the form of a
secondary scheduler of sorts somewhere in the VM. Hard problem.


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/