Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757194Ab0LHCPY (ORCPT ); Tue, 7 Dec 2010 21:15:24 -0500 Received: from mail-iw0-f172.google.com ([209.85.214.172]:35609 "EHLO mail-iw0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755820Ab0LHCPU (ORCPT ); Tue, 7 Dec 2010 21:15:20 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=NGSf21tnoAdoyFKu4c70BGXYC9aYIr+cz67RBL2X4NfcbaT7ZiyfB0GchuUGcSWbIe m/Bhdth57ZKzldxbkx/bsECHFcdykVY6cTQQ0GJaKQAnMu1yfWoa1gprbqZCMTbFrn1m NVrBHajnTJeOJRYvm7WqioVWKm2Mxt3YLWgq8= MIME-Version: 1.0 In-Reply-To: <20101208105637.5103de75.kamezawa.hiroyu@jp.fujitsu.com> References: <20101207144923.GB2356@cmpxchg.org> <20101207150710.GA26613@barrios-desktop> <20101207151939.GF2356@cmpxchg.org> <20101207152625.GB608@barrios-desktop> <20101207155645.GG2356@cmpxchg.org> <20101208095642.8128ab33.kamezawa.hiroyu@jp.fujitsu.com> <20101208105637.5103de75.kamezawa.hiroyu@jp.fujitsu.com> Date: Wed, 8 Dec 2010 11:15:19 +0900 Message-ID: Subject: Re: [PATCH v4 2/7] deactivate invalidated pages From: Minchan Kim To: KAMEZAWA Hiroyuki Cc: Johannes Weiner , Andrew Morton , Rik van Riel , KOSAKI Motohiro , linux-mm , LKML , Peter Zijlstra , Wu Fengguang , Nick Piggin , Mel Gorman , Balbir Singh Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2326 Lines: 76 On Wed, Dec 8, 2010 at 10:56 AM, KAMEZAWA Hiroyuki wrote: > On Wed, 8 Dec 2010 10:43:08 +0900 > Minchan Kim wrote: > >> Hi Kame, >> > Hi, > >> > I wonder ...how about adding "victim" list for "Reclaim" pages ? Then, we don't need >> > extra LRU rotation. >> >> It can make the code clean. >> As far as I think, victim list does following as. >> >> 1. select victim pages by strong hint >> 2. move the page from LRU to victim >> 3. reclaimer always peeks victim list before diving into LRU list. >> 4-1. If the victim pages is used by others or dirty, it can be moved >> into LRU, again or remain the page in victim list. >> If the page is remained victim, when do we move it into LRU again if >> the reclaimer continues to fail the page? > When sometone touches it. > >> We have to put the new rule. >> 4-2. If the victim pages isn't used by others and clean, we can >> reclaim the page asap. >> >> AFAIK, strong hints are just two(invalidation, readahead max window heuristic). >> I am not sure it's valuable to add new hierarchy(ie, LRU, victim, >> unevictable) for cleaning the minor codes. >> In addition, we have to put the new rule so it would make the LRU code >> complicated. >> I remember how unevictable feature merge is hard. >> > yes, it was hard. > >> But I am not against if we have more usecases. In this case, it's >> valuable to implement it although it's not easy. >> > > I wonder "victim list" can be used for something like Cleancache, when > we have very-low-latency backend devices. > And we may able to have page-cache-limit, which Balbir proposed as. Yes, I thought that, too. I think it would be a good feature in embedded system. > > - kvictimed? will move unmappedd page caches to victim list > This may work like a InactiveClean list which we had before and make > sizing easy. > Before further discuss, we need customer's confirm. We know very well it is very hard to merge if anyone doesn't use. Balbir, What do think about it? > Thanks, > -Kame > > > > -- Kind regards, Minchan Kim -- 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/