From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763322AbXGMIM3 (ORCPT ); Fri, 13 Jul 2007 04:12:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760200AbXGMIMU (ORCPT ); Fri, 13 Jul 2007 04:12:20 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:53301 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755948AbXGMIMS (ORCPT ); Fri, 13 Jul 2007 04:12:18 -0400 Subject: Re: [RFT][PATCH] mm: drop behind From: Peter Zijlstra To: Chris Snook Cc: Tim Pepper , linux-kernel , linux-mm , Fengguang Wu , riel , Andrew Morton , Rusty Russell In-Reply-To: <46967EE2.8020803@redhat.com> References: <1184007008.1913.45.camel@twins> <1184225086.20032.45.camel@twins> <46967EE2.8020803@redhat.com> Content-Type: text/plain Date: Fri, 13 Jul 2007 10:12:09 +0200 Message-Id: <1184314329.20032.70.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.10.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2007-07-12 at 15:20 -0400, Chris Snook wrote: > Then do what we do for FADV_SEQUENTIAL. With that advice, we double the > readahead window. We're already doing readahead, but we do a lot more > when we have the advice. NOREUSE should put much greater pressure on > the vm to drop these pages quickly, or perhaps simply eliminate the > heuristic evaluation of the access pattern and short-circuit straight to > dropping the pages. > > We should be encouraging application writers to actually use things like > fadvise when they can tune things more intelligently than kernel > heuristics can. I like this, I'll see what I can do.. :-)