From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: Slub support with PREEMPT_RT ?
Date: Thu, 18 Nov 2010 12:04:38 +0100
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Cc: Darren Hart <dvhart@linux.intel.com>,
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To: Jean-Michel Hautbois <jhautbois@gmail.com>
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On Thu, 2010-11-18 at 09:59 +0100, Jean-Michel Hautbois wrote:
> 
> My real question is the impact of SLUB compared to SLAB on the
> determinism of kmalloc usage and all caches.
> I did some tests using SLUB instead of SLAB on a small (MPC5200 /
> 400Mhz / 16k i-cache and 16k d-cache), and slub seems to be better.
> But I don't know if there is a possibility to tune SLAB in order to
> get good results. 

That's a pretty pointless idea, non of them are deterministic allocators
-- nor can they be, page allocation involves the whole vm reclaim path.

If you want determinism don't allocate memory.