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Date: Tue, 08 Apr 2008 00:05:52 +0300
From: Pekka Enberg <penberg@cs.helsinki.fi>
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To: Hugh Dickins <hugh@veritas.com>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl>,
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       Jens Axboe <jens.axboe@oracle.com>, "Rafael J. Wysocki" <rjw@sisk.pl>,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH] scsi: fix sense_slab/bio swapping livelock
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Pekka Enberg wrote:
> Although you weren't convinced by my arguments, I still have 
> difficulties understanding why this kind of bad behavior would be 
> acceptable in an embedded environment and why we don't need to fix it 
> for the SLOB case as well.
> 
> But you do bring up a good point of SLUB changing the behavior on OOM 
> situations for which SLAB_NOMERGE sounds like a good-enough stop-gap 
> measure for the short term. I would prefer some other fix even if it 
> means getting rid of slab merging competely (which would suck as it's 
> very nice for making memory footprint smaller).

I wonder if we can get away with a SLAB_IO flag that you can use to 
annotate caches that participate in writeout and the allocator could 
keep some spare pages around that can be handed out for them in case of 
OOM...

		Pekka