Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752808AbYGXGj2 (ORCPT ); Thu, 24 Jul 2008 02:39:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751097AbYGXGjV (ORCPT ); Thu, 24 Jul 2008 02:39:21 -0400 Received: from casper.infradead.org ([85.118.1.10]:56774 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751016AbYGXGjV (ORCPT ); Thu, 24 Jul 2008 02:39:21 -0400 Subject: Re: Odd swapping issue From: Peter Zijlstra To: David Newall Cc: Rafal Wijata , linux-kernel@vger.kernel.org In-Reply-To: <4887A000.30605@davidnewall.com> References: <488761F0.4040906@wijata.com> <1216835428.7257.194.camel@twins> <4887A000.30605@davidnewall.com> Content-Type: text/plain Date: Thu, 24 Jul 2008 08:39:25 +0200 Message-Id: <1216881565.7257.212.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 972 Lines: 27 On Thu, 2008-07-24 at 06:47 +0930, David Newall wrote: > Peter Zijlstra wrote: > > 16g ram on a 32bit kernel is stretching it... may I suggest running a > > 64bit kernel? > > > > Is it? Do we expect that behaviour with so much RAM? I expect your 32bit machine to go wonky after say 8gb,.. maybe even earlier for some workloads. The thing is, 32bit machines have less than 1gb of kernel memory - the more memory you have the less of that remains for system duties since such things as the page frame array grow with the number of physical pages present. Also, all such things as buffer cache reside in that tiny space. At some point the kernel itself is just going to run out of memory trying to manage your machine. -- 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/