Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262720AbUCRPwU (ORCPT ); Thu, 18 Mar 2004 10:52:20 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262721AbUCRPwU (ORCPT ); Thu, 18 Mar 2004 10:52:20 -0500 Received: from ppp-217-133-42-200.cust-adsl.tiscali.it ([217.133.42.200]:22921 "EHLO dualathlon.random") by vger.kernel.org with ESMTP id S262720AbUCRPwR (ORCPT ); Thu, 18 Mar 2004 10:52:17 -0500 Date: Thu, 18 Mar 2004 16:53:06 +0100 From: Andrea Arcangeli To: Rik van Riel Cc: linux-kernel@vger.kernel.org Subject: Re: 2.6.5-rc1-aa1 Message-ID: <20040318155306.GI2246@dualathlon.random> References: <20040318022201.GE2113@dualathlon.random> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.1i X-GPG-Key: 1024D/68B9CB43 13D9 8355 295F 4823 7C49 C012 DFA1 686E 68B9 CB43 X-PGP-Key: 1024R/CB4660B9 CC A0 71 81 F4 A0 63 AC C0 4B 81 1D 8C 15 C8 E5 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1872 Lines: 36 On Thu, Mar 18, 2004 at 10:32:58AM -0500, Rik van Riel wrote: > At that point we'll want to split the file-backed stuff off the filebacked stuff is already separated, what can be separated further is the preparation for the page->as.mapping support. > I'm kind of curious which one will end up better under > which workloads ;) I know of big iron critical workloads where mine will work better, though I agree for a desktop not runing kde the anonm is cheaper in terms of memory utilization (saves . andrea@dualathlon:~> egrep 'vm_area|anon_vma' /proc/slabinfo vm_area_struct 6613 8500 76 50 1 : tunables 120 60 8 : slabdata 170 170 0 anon_vma 2085 2250 12 250 1 : tunables 120 60 8 : slabdata 9 9 0 andrea@dualathlon:~> free total used free shared buffers cached Mem: 1031348 1014156 17192 0 18144 665052 -/+ buffers/cache: 330960 700388 Swap: 1028152 0 1028152 andrea@dualathlon:~> the anonmm would take 12*2085+6613*12 = 104k less in my 1G desktop loaded with my usual stuff (not really, the difference is less than 100k since anonmm takes quite some bytes, which is significant too if we count the kbytes like I'm doing), I believe those 100k may be worth it for the super high end workload swapping 8G on a 16G box with hundred of tasks each task with its own anonymous direct memory big chunk of memory, anon_vma will avoid checking all hundred MM for each anon page we swap, plus it gets mremap efficiently which sounds safer for the short term. - 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/