Date: Tue, 13 Dec 2005 14:23:46 -0800
From: Paul Jackson <pj@sgi.com>
To: Eric Dumazet <dada1@cosmosbay.com>
Cc: clameter@engr.sgi.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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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.

Time for me to learn more about rcu.

Thanks for raising this issue.

-- 
                  I won't rest till it's the best ...
                  Programmer, Linux Scalability
                  Paul Jackson <pj@sgi.com> 1.925.600.0401
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