Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757682AbXLUV4W (ORCPT ); Fri, 21 Dec 2007 16:56:22 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753568AbXLUV4N (ORCPT ); Fri, 21 Dec 2007 16:56:13 -0500 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:53026 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753254AbXLUV4N (ORCPT ); Fri, 21 Dec 2007 16:56:13 -0500 Date: Fri, 21 Dec 2007 13:56:11 -0800 (PST) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Ingo Molnar cc: Steven Rostedt , LKML , Andrew Morton , Linus Torvalds , Peter Zijlstra , Christoph Hellwig , "Rafael J. Wysocki" Subject: Re: Major regression on hackbench with SLUB (more numbers) In-Reply-To: <20071221163337.GA8660@elte.hu> Message-ID: References: <1197049846.1645.68.camel@localhost.localdomain> <20071211143336.GA17866@elte.hu> <20071221120908.GA15926@elte.hu> <20071221122628.GA18002@elte.hu> <20071221163337.GA8660@elte.hu> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1783 Lines: 38 On Fri, 21 Dec 2007, Ingo Molnar wrote: > > There are patches pending to address these issues. AFAICT Intel is > > testing if the regression is still there. There is no way for me to > > verify what is going on there and there is the constant difficulty of > > getting detailed information about what is going on at Intel. Every > > couple of month I get a result from that test. Its a really crappy > > situation where a lot of confusing information is passed around. > > of course there is a way to find out, and that's why i mailed you: fix > the hackbench regression and i'm quite sure you'll improve the TPC-C > numbers as well. It shows the same kind of overhead in the profile and > takes just a few seconds to run. Are your pending SLUB patches in > 2.6.24-rc5-mm1 already? The tests that I wrote emulate the test behavior that was described to me by me. The fixes in 2.6.24-rc5-mm1 improved those numbers. See http://lkml.org/lkml/2007/10/27/245 which I quoted earlier to you. However, I have no TPC-C setup here and from what I hear it takes weeks to run and requires a large support team for tuning. You can find the slab test suite for that at http://git.kernel.org/?p=linux/kernel/git/christoph/vm.git;a=shortlog;h=tests AFAICT the fixes in 2.6.25-rc5-mm1 result in double the alloc performance (fastpath) of SLAB. There are fixes that are not merged yet (the cpu alloc patchset) that seem to make that factor 3 because we can use the segment register to avoid per cpu array lookups in the fast path. -- 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/