From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from d03relay04.boulder.ibm.com (d03relay04.boulder.ibm.com [9.17.195.106]) by e35.co.us.ibm.com (8.13.8/8.13.8) with ESMTP id lBMKRf1m017210 for ; Sat, 22 Dec 2007 15:27:41 -0500 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d03relay04.boulder.ibm.com (8.13.8/8.13.8/NCO v8.7) with ESMTP id lBMKRZ8F104000 for ; Sat, 22 Dec 2007 13:27:40 -0700 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id lBMKRZhv014696 for ; Sat, 22 Dec 2007 13:27:35 -0700 Message-ID: <476D7334.4010301@linux.vnet.ibm.com> Date: Sun, 23 Dec 2007 01:57:32 +0530 From: Balbir Singh Reply-To: balbir@linux.vnet.ibm.com MIME-Version: 1.0 Subject: Re: [patch 00/20] VM pageout scalability improvements References: <20071218211539.250334036@redhat.com> In-Reply-To: <20071218211539.250334036@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Rik van Riel Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, lee.shermerhorn@hp.com List-ID: Rik van Riel wrote: > On large memory systems, the VM can spend way too much time scanning > through pages that it cannot (or should not) evict from memory. Not > only does it use up CPU time, but it also provokes lock contention > and can leave large systems under memory presure in a catatonic state. > Hi, Rik, I remember you mentioning that by large memory systems you mean systems with at-least 128GB, does this definition still hold? > This patch series improves VM scalability by: > > 1) making the locking a little more scalable > > 2) putting filesystem backed, swap backed and non-reclaimable pages > onto their own LRUs, so the system only scans the pages that it > can/should evict from memory > > 3) switching to SEQ replacement for the anonymous LRUs, so the > number of pages that need to be scanned when the system > starts swapping is bound to a reasonable number > > The noreclaim patches come verbatim from Lee Schermerhorn and > Nick Piggin. I have not taken a detailed look at them yet and > all I have done is fix the rejects against the latest -mm kernel. > Is there a consolidate patch available, it makes it easier to test. > I am posting this series now because I would like to get more > feedback, while I am studying and improving the noreclaim patches > myself. > What kind of tests show the problem? I'll try and review and test the code. -- Warm Regards, Balbir Singh Linux Technology Center IBM, ISTL -- 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