Date: Mon, 6 Aug 2007 12:11:13 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
cc: Daniel Phillips <phillips@phunq.net>, linux-kernel@vger.kernel.org,
       linux-mm@kvack.org, David Miller <davem@davemloft.net>,
       Andrew Morton <akpm@linux-foundation.org>,
       Daniel Phillips <phillips@google.com>,
       Pekka Enberg <penberg@cs.helsinki.fi>, Matt Mackall <mpm@selenic.com>,
       Lee Schermerhorn <Lee.Schermerhorn@hp.com>,
       Steve Dickson <SteveD@redhat.com>
Subject: Re: [PATCH 02/10] mm: system wide ALLOC_NO_WATERMARK
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On Mon, 6 Aug 2007, Peter Zijlstra wrote:

> > > Shudder. That can just be a desaster for NUMA. Both performance wise
> > > and logic wise. One cpuset being low on memory should not affect
> > > applications in other cpusets.
> 
> Do note that these are only PF_MEMALLOC allocations that will break the
> cpuset. And one can argue that these are not application allocation but
> system allocations.

This is global, global locking etc etc. On a large NUMA system this will 
cause significant delays. One fears that a livelock may result.

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