Re: [RFC][PATCH 0/2] Quicklist is slighly problematic.

From: Robin Holt
Date: Thu Aug 21 2008 - 09:45:49 EST


On Thu, Aug 21, 2008 at 08:18:24AM -0500, Christoph Lameter wrote:
> Robin Holt wrote:
>
> >> We removed this code because it frees a page before the TLB flush has been
> >> performed. This code segment was the reason that quicklists were not accepted
> >> for x86.
> >
> > How could we do this. It was a _HUGE_ problem on altix boxes. When you
> > started a jobs with a large number of MPI ranks, they would all start
> > from the shepherd process on a single node and the children would
> > migrate to a different cpu. Unless subsequent jobs used enough memory
> > to flush those remote quicklists, we would end up with a depleted node
> > that never reclaimed.
>
> Well I tried to get the quicklist stuff resolved at SGI multiple times last
> year when the early free before flush was discovered but there did not seem to
> be much interest at that point, so we dropped it.

Well, now that you dope slap me, I vaguely remember this. I also seem
to recall being very busy with other stuff and convincing myself that a
proper resolution would magically appear. Argh.

Sorry,
Robin
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