DomainKey-Signature: a=rsa-sha1; c=nofws;
        d=gmail.com; s=gamma;
        h=message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version
         :content-type:content-transfer-encoding:content-disposition
         :references:x-google-sender-auth;
        b=prOEvwf164V1ICoeRIK/Tiu4K0plAbldqi7EoRaFwJKyp9MngC1MDwREO9NPtJ7kgC
         pp1Tx4Fg443vVqiXeM0MTzYpmwOvCqE+4CLh0UZwDwYSElZBslHZhwYZ53gN9hI+wqp/
         WGr4zQADvqOlZ8kL+onTGftTbvnlWBCPpx8Nk=
Message-ID: <84144f020901140730l747b4e06j41fb8a35daeaf6c8@mail.gmail.com>
Date: Wed, 14 Jan 2009 17:30:48 +0200
From: "Pekka Enberg" <penberg@cs.helsinki.fi>
To: "Nick Piggin" <npiggin@suse.de>
Subject: Re: [patch] SLQB slab allocator
Cc: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>,
       "Lin Ming" <ming.m.lin@intel.com>,
       "Christoph Lameter" <cl@linux-foundation.org>, linux-mm@kvack.org,
       linux-kernel@vger.kernel.org,
       "Andrew Morton" <akpm@linux-foundation.org>,
       "Linus Torvalds" <torvalds@linux-foundation.org>
In-Reply-To: <20090114152207.GD25401@wotan.suse.de>
MIME-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
References: <20090114090449.GE2942@wotan.suse.de>
	 <84144f020901140253s72995188vb35a79501c38eaa3@mail.gmail.com>
	 <20090114114707.GA24673@wotan.suse.de>
	 <84144f020901140544v56b856a4w80756b90f5b59f26@mail.gmail.com>
	 <20090114142200.GB25401@wotan.suse.de>
	 <84144f020901140645o68328e01ne0e10ace47555e19@mail.gmail.com>
	 <20090114150900.GC25401@wotan.suse.de>
	 <20090114152207.GD25401@wotan.suse.de>
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1302
Lines: 26

Hi Nick,

On Wed, Jan 14, 2009 at 5:22 PM, Nick Piggin <npiggin@suse.de> wrote:
> And... IIRC, the Intel guys did make a stink but it wasn't considered
> so important or worthwhile to fix for some reason? Anyway, the fact is
> that it hadn't been fixed in SLUB. Hmm, I guess it is a significant
> failure of SLUB that it hasn't managed to replace SLAB by this point.

Again, not speaking for Christoph, but *I* do consider the regression
to be important and I do want it to be fixed. I have asked for a test
case to reproduce the regression and/or oprofile reports but have yet
to receive them. I did fix one regression I saw with the fio benchmark
but unfortunately it wasn't the same regression the Intel guys are
hitting. I suppose we're in limbo now because the people who are
affected by the regression can simply turn on CONFIG_SLAB.

In any case, I do agree that the inability to replace SLAB with SLUB
is a failure on the latter. I'm just not totally convinced that it's
because the SLUB code is unfixable ;).

                                Pekka
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/