From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2992617AbXCBQ7S (ORCPT ); Fri, 2 Mar 2007 11:59:18 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S2992619AbXCBQ7R (ORCPT ); Fri, 2 Mar 2007 11:59:17 -0500 Received: from smtp.osdl.org ([65.172.181.24]:34538 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2992617AbXCBQ7P (ORCPT ); Fri, 2 Mar 2007 11:59:15 -0500 Date: Fri, 2 Mar 2007 08:58:38 -0800 From: Andrew Morton To: Rik van Riel Cc: Mel Gorman , npiggin@suse.de, clameter@engr.sgi.com, mingo@elte.hu, jschopp@austin.ibm.com, arjan@infradead.org, torvalds@linux-foundation.org, mbligh@mbligh.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: The performance and behaviour of the anti-fragmentation related patches Message-Id: <20070302085838.bcf9099e.akpm@linux-foundation.org> In-Reply-To: <45E842F6.5010105@redhat.com> References: <20070301101249.GA29351@skynet.ie> <20070301160915.6da876c5.akpm@linux-foundation.org> <45E842F6.5010105@redhat.com> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.17; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 02 Mar 2007 10:29:58 -0500 Rik van Riel wrote: > Andrew Morton wrote: > > > And I'd judge that per-container RSS limits are of considerably more value > > than antifrag (in fact per-container RSS might be a superset of antifrag, > > in the sense that per-container RSS and containers could be abused to fix > > the i-cant-get-any-hugepages problem, dunno). > > The RSS bits really worry me, since it looks like they could > exacerbate the scalability problems that we are already running > into on very large memory systems. Using a zone-per-container or N-64MB-zones-per-container should actually move us in the direction of *fixing* any such problems. Because, to a first-order, the scanning of such a zone has the same behaviour as a 64MB machine. (We'd run into a few other problems, some related to the globalness of the dirty-memory management, but that's fixable). > Linux is *not* happy on 256GB systems. Even on some 32GB systems > the swappiness setting *needs* to be tweaked before Linux will even > run in a reasonable way. Please send testcases. From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 2 Mar 2007 08:58:38 -0800 From: Andrew Morton Subject: Re: The performance and behaviour of the anti-fragmentation related patches Message-Id: <20070302085838.bcf9099e.akpm@linux-foundation.org> In-Reply-To: <45E842F6.5010105@redhat.com> References: <20070301101249.GA29351@skynet.ie> <20070301160915.6da876c5.akpm@linux-foundation.org> <45E842F6.5010105@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Rik van Riel Cc: Mel Gorman , npiggin@suse.de, clameter@engr.sgi.com, mingo@elte.hu, jschopp@austin.ibm.com, arjan@infradead.org, torvalds@linux-foundation.org, mbligh@mbligh.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: On Fri, 02 Mar 2007 10:29:58 -0500 Rik van Riel wrote: > Andrew Morton wrote: > > > And I'd judge that per-container RSS limits are of considerably more value > > than antifrag (in fact per-container RSS might be a superset of antifrag, > > in the sense that per-container RSS and containers could be abused to fix > > the i-cant-get-any-hugepages problem, dunno). > > The RSS bits really worry me, since it looks like they could > exacerbate the scalability problems that we are already running > into on very large memory systems. Using a zone-per-container or N-64MB-zones-per-container should actually move us in the direction of *fixing* any such problems. Because, to a first-order, the scanning of such a zone has the same behaviour as a 64MB machine. (We'd run into a few other problems, some related to the globalness of the dirty-memory management, but that's fixable). > Linux is *not* happy on 256GB systems. Even on some 32GB systems > the swappiness setting *needs* to be tweaked before Linux will even > run in a reasonable way. Please send testcases. -- 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