Date: Tue, 13 Dec 2005 14:29:56 -0800 (PST)
From: Christoph Lameter <clameter@engr.sgi.com>
To: Paul Jackson <pj@sgi.com>
cc: Eric Dumazet <dada1@cosmosbay.com>, akpm@osdl.org,
       linux-kernel@vger.kernel.org, nickpiggin@yahoo.com.au,
       Simon.Derr@bull.net, ak@suse.de
Subject: Re: [PATCH] Cpuset: rcu optimization of page alloc hook
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On Tue, 13 Dec 2005, Paul Jackson wrote:

> Eric wrote:
> > struct kmem_cache  itself will be about 512*8 + some bytes
> > then for each cpu a 'struct array_cache' will be allocated (count 128 bytes 
> 
> Hmmm ... 'struct array_cache' looks to be about 6 integer words,
> so if that is the main per-CPU cost, the minimal cost of a slab
> cache (once created, before use) is about 24 bytes per cpu.
> 
> But whether its 24 or 128 bytes per cpu, that's a heavier weight
> hammer than is needed here.

The main per node costs is struct kmem_list3 on top of the array_cache.

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