From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753561AbWKDBmL (ORCPT ); Fri, 3 Nov 2006 20:42:11 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753564AbWKDBmL (ORCPT ); Fri, 3 Nov 2006 20:42:11 -0500 Received: from smtp.osdl.org ([65.172.181.4]:17041 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1753561AbWKDBmK (ORCPT ); Fri, 3 Nov 2006 20:42:10 -0500 Date: Fri, 3 Nov 2006 17:42:06 -0800 From: Andrew Morton To: Paul Jackson Cc: clameter@sgi.com, linux-kernel@vger.kernel.org Subject: Re: Avoid allocating during interleave from almost full nodes Message-Id: <20061103174206.53f2c49e.akpm@osdl.org> In-Reply-To: <20061103172605.e646352a.pj@sgi.com> References: <20061103134633.a815c7b3.akpm@osdl.org> <20061103143145.85a9c63f.akpm@osdl.org> <20061103172605.e646352a.pj@sgi.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, 3 Nov 2006 17:26:05 -0800 Paul Jackson wrote: > Andrew wrote: > > But in this application which you are proposing, any correlation with > > elapsed walltime is very slight. It's just the wrong baseline to use. > > What is the *sense* in it? > > Ah - but time is cheap as dirt, and scales like the common cold virus. > That makes it sinfully attractive for secondary affect placement cache > hints like this. > > What else would you suggest? > > Same question applies, I suppose, to my zonelist caching patch that is > sitting in your *-mm patch stack, where you also had doubts about using > wall clock time to decay the fullnode hints. Depends what it's doing. "number of pages allocated" would be a good "clock" to use in the VM. Or pages scanned. Or per-cpu-pages reloads. Something which adjusts to what's going on.