From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with SMTP id C782E6B0089 for ; Tue, 7 Dec 2010 21:02:24 -0500 (EST) Received: from m3.gw.fujitsu.co.jp ([10.0.50.73]) by fgwmail7.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id oB822LRa004376 for (envelope-from kamezawa.hiroyu@jp.fujitsu.com); Wed, 8 Dec 2010 11:02:21 +0900 Received: from smail (m3 [127.0.0.1]) by outgoing.m3.gw.fujitsu.co.jp (Postfix) with ESMTP id 800D245DE56 for ; Wed, 8 Dec 2010 11:02:21 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (s3.gw.fujitsu.co.jp [10.0.50.93]) by m3.gw.fujitsu.co.jp (Postfix) with ESMTP id 5879445DE5F for ; Wed, 8 Dec 2010 11:02:21 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id 4C6E2E18001 for ; Wed, 8 Dec 2010 11:02:21 +0900 (JST) Received: from m105.s.css.fujitsu.com (m105.s.css.fujitsu.com [10.249.87.105]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id 104B31DB8038 for ; Wed, 8 Dec 2010 11:02:21 +0900 (JST) Date: Wed, 8 Dec 2010 10:56:37 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [PATCH v4 2/7] deactivate invalidated pages Message-Id: <20101208105637.5103de75.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: 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> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Minchan Kim Cc: Johannes Weiner , Andrew Morton , Rik van Riel , KOSAKI Motohiro , linux-mm , LKML , Peter Zijlstra , Wu Fengguang , Nick Piggin , Mel Gorman List-ID: 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. - kvictimed? will move unmappedd page caches to victim list This may work like a InactiveClean list which we had before and make sizing easy. Thanks, -Kame -- 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/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org