Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758086AbZD3IMi (ORCPT ); Thu, 30 Apr 2009 04:12:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752290AbZD3IMV (ORCPT ); Thu, 30 Apr 2009 04:12:21 -0400 Received: from cmpxchg.org ([85.214.51.133]:45903 "EHLO cmpxchg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751706AbZD3IMU (ORCPT ); Thu, 30 Apr 2009 04:12:20 -0400 Date: Thu, 30 Apr 2009 10:10:29 +0200 From: Johannes Weiner To: Rik van Riel Cc: KOSAKI Motohiro , Peter Zijlstra , Elladan , linux-kernel@vger.kernel.org, tytso@mit.edu, linux-mm@kvack.org Subject: Re: [PATCH] vmscan: evict use-once pages first (v3) Message-ID: <20090430081029.GA23231@cmpxchg.org> References: <20090428044426.GA5035@eskimo.com> <20090428192907.556f3a34@bree.surriel.com> <1240987349.4512.18.camel@laptop> <20090429114708.66114c03@cuia.bos.redhat.com> <2f11576a0904290907g48e94e74ye97aae593f6ac519@mail.gmail.com> <20090429131436.640f09ab@cuia.bos.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090429131436.640f09ab@cuia.bos.redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1216 Lines: 28 On Wed, Apr 29, 2009 at 01:14:36PM -0400, Rik van Riel wrote: > When the file LRU lists are dominated by streaming IO pages, > evict those pages first, before considering evicting other > pages. > > This should be safe from deadlocks or performance problems > because only three things can happen to an inactive file page: > 1) referenced twice and promoted to the active list > 2) evicted by the pageout code > 3) under IO, after which it will get evicted or promoted > > The pages freed in this way can either be reused for streaming > IO, or allocated for something else. If the pages are used for > streaming IO, this pageout pattern continues. Otherwise, we will > fall back to the normal pageout pattern. > > Signed-off-by: Rik van Riel Although Elladan didn't test this exact patch, he reported on v2 that the general idea of scanning active files only when they exceed the inactive set works. Acked-by: Johannes Weiner -- 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/