lkml.org 
[lkml]   [2012]   [May]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 0/6] mempolicy memory corruption fixlet
On Wed, May 30, 2012 at 01:34:21PM -0500, Christoph Lameter wrote:
> On Wed, 30 May 2012, Linus Torvalds wrote:
>
> > On Wed, May 30, 2012 at 2:02 AM, <kosaki.motohiro@gmail.com> wrote:
> > >
> > > So, I think we should reconsider about shared mempolicy completely.
> >
> > Quite frankly, I'd prefer that approach. The code is subtle and
> > horribly bug-fraught, and I absolutely detest the way it looks too.
> > Reading your patches was actually somewhat painful.
>
> It is so bad mostly because the integration of shared memory policies with
> cpusets is not really working. Using either in isolation is ok especially
> shared mempolicies do not play well with cpusets.

Yes the cpusets did some horrible things.

I always regretted that cpusets were no done with custom node lists.
That would have been much cleaner and also likely faster than what we have.

> > If we could just remove the support for it entirely, that would be
> > *much* preferable to continue working with this code.
>
> Well shm support needs memory policies to spread data across nodes etc.
> AFAICT support was put in due to requirements to support large database
> vendors (oracle). Andi?

Yes we need shared policy for the big databases.

Maybe we could stop supporting cpusets with that though. Not sure they
really use that.

> Its not going to be easy to remove.

Shared policies? I don't think you can remove them.
cpusets+shared policy? maybe, but still will be hard.

-Andi

>

--
ak@linux.intel.com -- Speaking for myself only.


\
 
 \ /
  Last update: 2012-05-30 21:01    [W:0.903 / U:0.008 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site