From: Andi Kleen <ak@suse.de>
To: Nick Piggin <nickpiggin@yahoo.com.au>
Subject: Re: [PATCH] use local_t for page statistics
Date: Sat, 7 Jan 2006 04:01:47 +0100
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Cc: Andrew Morton <akpm@osdl.org>, Benjamin LaHaise <bcrl@kvack.org>,
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On Saturday 07 January 2006 03:52, Nick Piggin wrote:

> No. On many load/store architectures there is no good way to do local_t,
> so something like ppc32 or ia64 just uses all atomic operations for

well, they're just broken and need to be fixed to not do that.

Also I bet with some tricks a seqlock like setup could be made to work.

> local_t, and ppc64 uses 3 counters per-cpu thus tripling the cache
> footprint.

and ppc64 has big caches so this also shouldn't be a problem.

-Andi
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