From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with ESMTP id 6B3B66B003D for ; Thu, 30 Apr 2009 04:12:15 -0400 (EDT) Date: Thu, 30 Apr 2009 10:10:29 +0200 From: Johannes Weiner 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: owner-linux-mm@kvack.org To: Rik van Riel Cc: KOSAKI Motohiro , Peter Zijlstra , Elladan , linux-kernel@vger.kernel.org, tytso@mit.edu, linux-mm@kvack.org List-ID: 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, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org