From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id E10ED5F0001 for ; Tue, 3 Feb 2009 06:28:56 -0500 (EST) Date: Tue, 3 Feb 2009 11:28:52 +0000 From: Mel Gorman Subject: Re: [patch] SLQB slab allocator (try 2) Message-ID: <20090203112852.GJ9840@csn.ul.ie> References: <20090123154653.GA14517@wotan.suse.de> <1232959706.21504.7.camel@penberg-laptop> <20090203101205.GF9840@csn.ul.ie> <200902032136.26022.nickpiggin@yahoo.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <200902032136.26022.nickpiggin@yahoo.com.au> Sender: owner-linux-mm@kvack.org To: Nick Piggin Cc: Pekka Enberg , Nick Piggin , Linux Memory Management List , Linux Kernel Mailing List , Andrew Morton , Lin Ming , "Zhang, Yanmin" , Christoph Lameter List-ID: On Tue, Feb 03, 2009 at 09:36:24PM +1100, Nick Piggin wrote: > On Tuesday 03 February 2009 21:12:06 Mel Gorman wrote: > > On Mon, Jan 26, 2009 at 10:48:26AM +0200, Pekka Enberg wrote: > > > Hi Nick, > > > > > > On Fri, 2009-01-23 at 16:46 +0100, Nick Piggin wrote: > > > > Since last time, fixed bugs pointed out by Hugh and Andi, cleaned up > > > > the code suggested by Ingo (haven't yet incorporated Ingo's last > > > > patch). > > > > > > > > Should have fixed the crash reported by Yanmin (I was able to reproduce > > > > it on an ia64 system and fix it). > > > > > > > > Significantly reduced static footprint of init arrays, thanks to Andi's > > > > suggestion. > > > > > > > > Please consider for trial merge for linux-next. > > > > > > I merged a the one you resent privately as this one didn't apply at all. > > > The code is in topic/slqb/core branch of slab.git and should appear in > > > linux-next tomorrow. > > > > > > Testing and especially performance testing is welcome. If any of the HPC > > > people are reading this, please do give SLQB a good beating as Nick's > > > plan is to replace both, SLAB and SLUB, with it in the long run.As > > > Christoph has expressed concerns over latency issues of SLQB, I suppose > > > it would be interesting to hear if it makes any difference to the > > > real-time folks. > > > > The HPC folks care about a few different workloads but speccpu is one that > > shows up. I was in the position to run tests because I had put together > > the test harness for a paper I spent the last month writing. This mail > > shows a comparison between slab, slub and slqb for speccpu2006 running a > > single thread and sysbench ranging clients from 1 to 4*num_online_cpus() > > (16 in both cases). Additional tests were not run because just these two > > take one day per kernel to complete. Results are ratios to the SLAB figures > > and based on an x86-64 and ppc64 machine. > > Hi Mel, > > This is very nice, thanks for testing. SLQB and SLUB are quite similar > in a lot of cases, which indeed could be explained by cacheline placement > (both of these can allocate down to much smaller sizes, and both of them > also put metadata directly in free object memory rather than external > locations). > > But it will be interesting to try looking at some of the tests where > SLQB has larger regressions, so that might give me something to go on > if I can lay my hands on speccpu2006... > > I'd be interested to see how slub performs if booted with slub_min_objects=1 > (which should give similar order pages to SLAB and SLQB). > Just to clarify on this last point, do you mean slub_max_order=0 to force order-0 allocations in SLUB? -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org