From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with SMTP id 999666B0047 for ; Fri, 20 Mar 2009 12:07:00 -0400 (EDT) Received: from localhost (smtp.ultrahosting.com [127.0.0.1]) by smtp.ultrahosting.com (Postfix) with ESMTP id 50EE782C9FB for ; Fri, 20 Mar 2009 12:14:53 -0400 (EDT) Received: from smtp.ultrahosting.com ([74.213.174.254]) by localhost (smtp.ultrahosting.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 1sHo3FCS1r+H for ; Fri, 20 Mar 2009 12:14:47 -0400 (EDT) Received: from qirst.com (unknown [74.213.171.31]) by smtp.ultrahosting.com (Postfix) with ESMTP id 0B81582C9FF for ; Fri, 20 Mar 2009 12:14:42 -0400 (EDT) Date: Fri, 20 Mar 2009 12:04:42 -0400 (EDT) From: Christoph Lameter Subject: Re: [PATCH 00/25] Cleanup and optimise the page allocator V5 In-Reply-To: <20090320153723.GO24586@csn.ul.ie> Message-ID: References: <1237543392-11797-1-git-send-email-mel@csn.ul.ie> <20090320153723.GO24586@csn.ul.ie> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: Mel Gorman Cc: Linux Memory Management List , KOSAKI Motohiro , Nick Piggin , Linux Kernel Mailing List , Lin Ming , Zhang Yanmin , Peter Zijlstra , Andrew Morton List-ID: On Fri, 20 Mar 2009, Mel Gorman wrote: > hmm, I'm missing something in your reasoning. The contention I saw for > zone->lru_lock > > &zone->lru_lock 37350 [] ____pagevec_lru_add+0x9c/0x172 > &zone->lru_lock 55423 [] release_pages+0x10a/0x21b > &zone->lru_lock 402 [] activate_page+0x4f/0x147 > &zone->lru_lock 6 [] put_page+0x94/0x122 > > So I just assumed it was LRU pages being taken off and freed that was > causing the contention. Can SLUB affect that? No. But it can affect the taking of the zone lock. > Maybe you meant zone->lock and SLUB could tune buffers more to avoid > that if that lock was hot. That is one alternative but the later patches > proposed an alternative whereby high-order and compound pages could be > stored on the PCP lists. Compound only really helps SLUB but high-order > also helped stacks, signal handlers and the like so it seemed like a > good idea one way or the other. Course, this meant a search of the PCP > lists or increasing the size of the PCP structure - swings and > roundabouts :/ Maybe include those as well? Its good stuff. -- 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