From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2992562AbXCWUjE (ORCPT ); Fri, 23 Mar 2007 16:39:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S2992563AbXCWUjE (ORCPT ); Fri, 23 Mar 2007 16:39:04 -0400 Received: from agminet01.oracle.com ([141.146.126.228]:29271 "EHLO agminet01.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2992562AbXCWUjD (ORCPT ); Fri, 23 Mar 2007 16:39:03 -0400 Message-ID: <46043A66.7030102@oracle.com> Date: Fri, 23 Mar 2007 13:36:54 -0700 From: Randy Dunlap User-Agent: Thunderbird 1.5.0.5 (X11/20060719) MIME-Version: 1.0 To: Kyle Moffett CC: Andrew Morton , "H. Peter Anvin" , "J.H." , kernel list Subject: Re: [PATCH] sysctl: vfs_cache_divisor References: <20061214223718.GA3816@elf.ucw.cz> <20061216094421.416a271e.randy.dunlap@oracle.com> <20061216095702.3e6f1d1f.akpm@osdl.org> <458434B0.4090506@oracle.com> <1166297434.26330.34.camel@localhost.localdomain> <20061219063413.GI24090@1wt.eu> <1166511171.26330.120.camel@localhost.localdomain> <20070106103331.48150aed.randy.dunlap@oracle.com> <459FF60D.7080901@zytor.com> <1168112266.2821.2.camel@entropy> <20070106121301.d07de0c9.akpm@osdl.org> <45A0041F.4060903@zytor.com> <20070319122740.286f602e.randy.dunlap@oracle.com> <20070319133613.9f4881db.akpm@linux-foundation.org> <45FEF5BC.90809@oracle.com> <45FF6189.9080508@zytor.com> <20070321160132.983812ac.randy.dunlap@oracle.com> <20070321161140.457a3cd7.akpm@linux-foundation.org> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: AAAAAQAAAAI= X-Brightmail-Tracker: AAAAAQAAAAI= X-Whitelist: TRUE X-Whitelist: TRUE Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Kyle Moffett wrote: > On Mar 21, 2007, at 19:11:40, Andrew Morton wrote: >> On Wed, 21 Mar 2007 16:01:32 -0700 Randy Dunlap >> wrote: >>> I prefer the fixed-point values for pressure and dirty* to having >>> duplicated entries for each of them. I'll proceed with that idea. >> >> Problem is, if a read of /proc/sys/vm/dirty_ratio is changed to return >> 7.457 then existing userspace might get confused. >> >> This might be acceptable if we are careful to ensure that reads of >> /proc/sys/vm/dirty_ratio will always return an integer if it was >> previously initialised with an integer. > > What about instead adding support for fractions (IE: "1/1000") in > /proc/sys/vm/dirty_ratio? If the denominator is 100, the default, then > it prints in the form "$NUMERATOR", otherwise it prints answers of the > form "$NUMERATOR/$DENOMINATOR". Input could be of either form, with the > kernel auto-setting the denominator to 100 if none is specified. Hi, That makes a lot of sense to me. It gives us finer-grained control without having to support fixed-point data. I've been working on the fixed-point data patch, but I'm going to give this method some time also, to see how it looks in code (instead of just thinking about it). Thanks. -- ~Randy *** Remember to use Documentation/SubmitChecklist when testing your code ***