Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757040AbZCTPD3 (ORCPT ); Fri, 20 Mar 2009 11:03:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754504AbZCTPDV (ORCPT ); Fri, 20 Mar 2009 11:03:21 -0400 Received: from smtp.ultrahosting.com ([74.213.174.254]:49284 "EHLO smtp.ultrahosting.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753051AbZCTPDU (ORCPT ); Fri, 20 Mar 2009 11:03:20 -0400 Date: Fri, 20 Mar 2009 11:00:42 -0400 (EDT) From: Christoph Lameter X-X-Sender: cl@qirst.com To: Mel Gorman cc: Linux Memory Management List , KOSAKI Motohiro , Nick Piggin , Linux Kernel Mailing List , Lin Ming , Zhang Yanmin , Peter Zijlstra , Andrew Morton Subject: Re: [PATCH 00/25] Cleanup and optimise the page allocator V5 In-Reply-To: <1237543392-11797-1-git-send-email-mel@csn.ul.ie> Message-ID: References: <1237543392-11797-1-git-send-email-mel@csn.ul.ie> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) 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: 1070 Lines: 21 On Fri, 20 Mar 2009, Mel Gorman wrote: > The lock contention on some machines goes up for the the zone->lru_lock > and zone->lock locks which can regress some workloads even though others on > the same machine still go faster. For netperf, a lock called slock-AF_INET > seemed very important although I didn't look too closely other than noting > contention went up. The zone->lock gets hammered a lot by high order allocs > and frees coming from SLUB which are not covered by the PCP allocator in > this patchset. zone->lru_lock goes up is less clear but as it's page cache > releases but overall contention may be up because CPUs are spending less > time with interrupts disabled and more time trying to do real work but > contending on the locks. We can tune SLUB to buffer more pages if the lru lock becomes too hot. -- 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/