From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: [RFC][PATCH 1/6] mm: slab allocation fairness
Date: Fri, 01 Dec 2006 12:28:47 +0100
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	David Miller <davem@davemloft.net>
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To: Christoph Lameter <clameter@sgi.com>
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On Thu, 2006-11-30 at 11:33 -0800, Christoph Lameter wrote:
> On Thu, 30 Nov 2006, Peter Zijlstra wrote:
> 
> > No, the forced allocation is to test the allocation hardness at that
> > point in time. I could not think of another way to test that than to
> > actually to an allocation.
> 
> Typically we do this by checking the number of free pages in a zone 
> compared to the high low limits. See mmzone.h.

This doesn't work under high load because of direct reclaim. And if I go
run direct reclaim to test if I can raise the free pages level to an
acceptable level for the given gfp flags, I might as well do the whole
allocation.