Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932202AbWAAKiI (ORCPT ); Sun, 1 Jan 2006 05:38:08 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932206AbWAAKiI (ORCPT ); Sun, 1 Jan 2006 05:38:08 -0500 Received: from amsfep14-int.chello.nl ([213.46.243.21]:54806 "EHLO amsfep14-int.chello.nl") by vger.kernel.org with ESMTP id S932202AbWAAKiH (ORCPT ); Sun, 1 Jan 2006 05:38:07 -0500 Subject: Re: [PATCH 6/9] clockpro-clockpro.patch From: Peter Zijlstra To: Marcelo Tosatti Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton , Christoph Lameter , Wu Fengguang , Nick Piggin , Marijn Meijles , Rik van Riel In-Reply-To: <20051231224021.GA5184@dmt.cnet> References: <20051230223952.765.21096.sendpatchset@twins.localnet> <20051230224312.765.58575.sendpatchset@twins.localnet> <20051231224021.GA5184@dmt.cnet> Content-Type: text/plain Date: Sun, 01 Jan 2006 11:37:34 +0100 Message-Id: <1136111854.17853.77.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.4.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1492 Lines: 38 On Sat, 2005-12-31 at 20:40 -0200, Marcelo Tosatti wrote: > On Fri, Dec 30, 2005 at 11:43:34PM +0100, Peter Zijlstra wrote: > > > > From: Peter Zijlstra > > Peter, > > I tried your "scan-shared.c" proggy which loops over 140M of a file > using mmap (on a 128MB box). The number of loops was configured to "5". > > The amount of major/minor pagefaults was exactly the same between > vanilla and clockpro, isnt the clockpro algorithm supposed to be > superior than LRU in such "sequential scan of MEMSIZE+1" cases? yes it should, hmm, have to look at that then. What should happen is that nr_cold_target should drop to the bare minimum, which effectivly pins all hot pages and only rotates the few cold pages. > Oh well, to be sincere, I still haven't understood what makes CLOCK-Pro > use inter reference distance instead of recency, given that its a simple > CLOCK using reference bits (but with three clocks instead of one). > > But thats probably just my ignorance, need to study more. The reuse distance is in PG_test. Please see the clockpro-documentation patch, which should explain this. If its still not clear after that let me know, I'll be more verbose then. -- Peter Zijlstra - 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/