From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758157Ab2DJACK (ORCPT ); Mon, 9 Apr 2012 20:02:10 -0400 Received: from forward6.mail.yandex.net ([77.88.60.125]:56932 "EHLO forward6.mail.yandex.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750858Ab2DJACJ (ORCPT ); Mon, 9 Apr 2012 20:02:09 -0400 X-Greylist: delayed 673 seconds by postgrey-1.27 at vger.kernel.org; Mon, 09 Apr 2012 20:02:09 EDT From: Alexey Ivanov To: Rik van Riel Cc: "gnehzuil.lzheng@gmail.com" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , yinghan@google.com In-Reply-To: <4F8326FD.8020507@redhat.com> References: <37371333672160@webcorp7.yandex-team.ru> <4F7E9854.1020904@gmail.com> <12701333991475@webcorp7.yandex-team.ru> <4F8326FD.8020507@redhat.com> Subject: Re: mapped pagecache pages vs unmapped pages MIME-Version: 1.0 Message-Id: <8041334015453@webcorp4.yandex-team.ru> Date: Tue, 10 Apr 2012 03:50:53 +0400 X-Mailer: Yamail [ http://yandex.ru ] 5.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=koi8-r Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Did you consider making this ratio tunable, at least manually(i.e. via sysctl)? I suppose we are not the only ones with almost-whole-ram-mmaped workload. 09.04.2012, 22:56, "Rik van Riel" : > On 04/09/2012 01:11 PM, Alexey Ivanov wrote: > >> šThanks for the hint! >> >> šCan anyone clarify the reason of not using zone->inactive_ratio in inactive_file_is_low_global()? > > New anonymous pages start out on the active anon list, and > are always referenced. šIf memory fills up, they may end > up getting moved to the inactive anon list; being referenced > while on the inactive anon list is enough to get them promoted > back to the active list. > > New file pages start out on the INACTIVE file list, and > start their lives not referenced at all. Due to readahead > extra reads, many file pages may never be referenced. > > Only file pages that are referenced twice make it onto > the active list. > > This means the inactive file list has to be large enough > for all the readahead buffers, and give pages enough time > on the list that frequently accessed ones can get accessed > twice and promoted. > > http://linux-mm.org/PageReplacementDesign > > -- > All rights reversed -- Alexey Ivanov Yandex Search Admin Team