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Date: Tue, 11 Mar 2008 16:45:48 +0200
From: "Pekka Enberg" <penberg@cs.helsinki.fi>
To: "Nick Piggin" <nickpiggin@yahoo.com.au>
Subject: Re: [RFC PATCH] Implement slub fastpath with sequence number
Cc: "Mathieu Desnoyers" <mathieu.desnoyers@polymtl.ca>,
       "Christoph Lameter" <clameter@sgi.com>, linux-kernel@vger.kernel.org
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Hi Nick,

On Tue, Mar 11, 2008 at 11:41 AM, Nick Piggin <nickpiggin@yahoo.com.au> wrote:
>  Wow. I applaud the effort to micro optimise things ;)
>
>  But I hope this doesn't get merged until macro-regressions in SLUB
>  are verified to be fixed. It's pretty clear that SLUB's problem is
>  not fastpath performance, so I think this would be premature
>  optimisation.

What regressions are you referring to? The SLAB_HWCACHE_ALIGN
regression patch you sent is being merged. What else?

And FWIW, I don't like the patch because it makes the code very hairy.
But I don't see why we shouldn't merge SLUB fast-path optimizations if
they're clean and you have the numbers to show it's a gain even if
there are other remaining regressions.