From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Pekka Enberg" Subject: Re: Mainline kernel OLTP performance update Date: Fri, 16 Jan 2009 12:55:30 +0200 Message-ID: <84144f020901160255i530755bboc07750a61240d4bf@mail.gmail.com> References: <200901162121.09128.nickpiggin@yahoo.com.au> <84144f020901160231k9e896d2o672079c1a2973632@mail.gmail.com> <200901162142.51306.nickpiggin@yahoo.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from fg-out-1718.google.com ([72.14.220.158]:61726 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755050AbZAPKze (ORCPT ); Fri, 16 Jan 2009 05:55:34 -0500 In-Reply-To: <200901162142.51306.nickpiggin@yahoo.com.au> Content-Disposition: inline Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Nick Piggin Cc: Matthew Wilcox , Andrew Morton , "Wilcox, Matthew R" , chinang.ma@intel.com, linux-kernel@vger.kernel.org, sharad.c.tripathi@intel.com, arjan@linux.intel.com, andi.kleen@intel.com, suresh.b.siddha@intel.com, harita.chilukuri@intel.com, douglas.w.styner@intel.com, peter.xihong.wang@intel.com, hubert.nueckel@intel.com, chris.mason@oracle.com, srostedt@redhat.com, linux-scsi@vger.kernel.org, Andrew Vasquez , Anirban Chakraborty , Christoph Lameter Hi Nick, On Fri, Jan 16, 2009 at 12:42 PM, Nick Piggin wrote: >> I don't have the exact config for the previous tests but it's was just >> my laptop regular config whereas the new tests are x86-64 defconfig. >> So I think I'm just hitting some of the other OLTP regressions here, >> aren't I? There's some scheduler related options such as >> CONFIG_GROUP_SCHED and CONFIG_FAIR_GROUP_SCHED enabled in defconfig >> that I didn't have in the original tests. I can try without them if >> you want but I'm not sure it's relevant for SLAB vs SLUB tests. > > Oh no that's fine. It just looked like you repeated the test but > with lockdep disabled (and no other changes). Right. In any case, I am still unable to reproduce the OLTP issue and I've seen SLUB beat SLAB on my machine in most of the benchmarks you've posted. So I have very mixed feelings about SLQB. It's very nice that it works for OLTP but we still don't have much insight (i.e. numbers) on why it's better. I'm also bit worried if SLQB has gotten enough attention from the NUMA and HPC folks that brought us SLUB. The good news is that SLQB can replace SLAB so either way, we're not going to end up with four allocators. Whether it can replace SLUB remains to be seen. Pekka