From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750734AbWKBEFI (ORCPT ); Wed, 1 Nov 2006 23:05:08 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751179AbWKBEFI (ORCPT ); Wed, 1 Nov 2006 23:05:08 -0500 Received: from mx2.suse.de ([195.135.220.15]:50639 "EHLO mx2.suse.de") by vger.kernel.org with ESMTP id S1750734AbWKBEFE (ORCPT ); Wed, 1 Nov 2006 23:05:04 -0500 To: Mel Gorman Cc: linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/11] Avoiding fragmentation with subzone groupings v26 References: <20061101111620.18798.34778.sendpatchset@skynet.skynet.ie> From: Andi Kleen Date: 02 Nov 2006 05:04:57 +0100 In-Reply-To: <20061101111620.18798.34778.sendpatchset@skynet.skynet.ie> Message-ID: User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Mel Gorman writes: > > Our tests show that about 60-70% of physical memory can be allocated on > a desktop after a few days uptime. In benchmarks and stress tests, we are > finding that 80% of memory is available as contiguous blocks at the end of > the test. To compare, a standard kernel was getting < 1% of memory as large > pages on a desktop and about 8-12% of memory as large pages at the end of > stress tests. If you don't have a fixed limit on the unreclaimable memory you could still get into a situation where all memory is fragmented and unreclaimable, right? It might be much harder to hit, but we have so many users that at least a few will eventually. > Performance tests are within 0.1% for kbuild on a number of test machines. aim9 > is usually within 1% 1% is a lot. -Andi