Subject: Re: [BUG] rebuild_sched_domains considered dangerous

From: Peter Zijlstra <[email-masked]>
Date: Fri, 03 Jun 2011 16:47:49 +0200

On Wed, 2011-05-11 at 11:17 -0500, Jesse Larrew wrote:
> > I would really like to see both patch-sets together. Also, I'm not
> at
> > all convinced its a sane thing to do. Pretty much all NUMA aware
> > software I know of assumes that CPU<->NODE relations are static,
> > breaking that in kernel renders all existing software broken.
> >=20
>=20
> I suspect that's true. Then again, shouldn't it be the capabilities of
> the hardware that dictates what the software does, rather than the
> other way around?=20

Wish that were true, we wouldn't be all constrained by all this legacy
software.. ;-)

Anyway, there's plenty of CPU<->NODE assumptions in the kernel as well,
fixing those will be 'interesting' at best, as for userspace, since its
a user-driven tool revamping the topology the user gets to keep the
pieces when he runs that while some NUMA aware proglet is running.