From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754811AbYIVW0q (ORCPT ); Mon, 22 Sep 2008 18:26:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753607AbYIVW0i (ORCPT ); Mon, 22 Sep 2008 18:26:38 -0400 Received: from smtp-out.google.com ([216.239.33.17]:61186 "EHLO smtp-out3.google.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753557AbYIVW0h (ORCPT ); Mon, 22 Sep 2008 18:26:37 -0400 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=message-id:date:from:to:subject:cc:in-reply-to: mime-version:content-type:content-transfer-encoding: content-disposition:references:x-gmailtapped-by; b=pqndwz1t49RLNf0I1uji2Lo8gcO9Z94Egq4zzsFqRJRiT2rNN1YO/670uq1z7Ltrd Qozw95SZCTq9+ZSL7WBiA== Message-ID: <532480950809221526k70fa28edx1d542a9c8a44f810@mail.gmail.com> Date: Mon, 22 Sep 2008 15:26:17 -0700 From: "Michael Rubin" To: "Andrew Morton" Subject: Re: [RFC] [PATCH -mm 0/2] memcg: per cgroup dirty_ratio Cc: righi.andrea@gmail.com, balbir@linux.vnet.ibm.com, menage@google.com, kamezawa.hiroyu@jp.fujitsu.com, dave@linux.vnet.ibm.com, chlunde@ping.uio.no, dpshah@google.com, eric.rannaud@gmail.com, fernando@oss.ntt.co.jp, agk@sourceware.org, m.innocenti@cineca.it, s-uchida@ap.jp.nec.com, ryov@valinux.co.jp, matt@bluehost.com, dradford@bluehost.com, containers@lists.linux-foundation.org, linux-kernel@vger.kernel.org In-Reply-To: <20080912161050.5b6b4065.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <1221232192-13553-1-git-send-email-righi.andrea@gmail.com> <20080912131816.e0cfac7a.akpm@linux-foundation.org> <48CAF583.8060406@gmail.com> <20080912161050.5b6b4065.akpm@linux-foundation.org> X-GMailtapped-By: 172.24.198.88 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently the problme we are hitting is that we cannot specify pdflush to have background limits less than 1% of memory. I am currently finishing up a patch right now that adds a dirty_ratio_millis interface. I hope to submit the patch to LKML by the end of the week. The idea is that we don't want to break backwards compatibility and we also don't want to have two conflicting knobs in the sysctl or /proc/sys/vm/ space. I thought adding a new knob for those who want to specify finer grained functionality was a compromise. So the patch has a vm_dirty_ratio and a vm_dirty_ratio_millis interface. The first to specify 0-100% and the second to specify .0 to .999%. So to represent 0.125% of RAM we set vm_dirty_ratio = 0 vm_dirty_ratio_millis = 125 The same for the background_ratio. Any feedback? mrubin On Fri, Sep 12, 2008 at 4:10 PM, Andrew Morton wrote: > On Sat, 13 Sep 2008 01:04:35 +0200 > Andrea Righi wrote: > >> BTW why not use a simple dirty-ratio-in-bytes? > > s/ratio/amount/ ;) > > No particular reason - I haven't really thought about it frankly. > > A "ratio" might make more sense in a containerised setup, particularly > if the container can be resized on the fly. >