From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750760AbWHRHBV (ORCPT ); Fri, 18 Aug 2006 03:01:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750770AbWHRHBV (ORCPT ); Fri, 18 Aug 2006 03:01:21 -0400 Received: from brick.kernel.dk ([62.242.22.158]:10299 "EHLO kernel.dk") by vger.kernel.org with ESMTP id S1750760AbWHRHBU (ORCPT ); Fri, 18 Aug 2006 03:01:20 -0400 Date: Fri, 18 Aug 2006 09:03:15 +0200 From: Jens Axboe To: Andrew Morton Cc: David Chinner , Neil Brown , linux-kernel@vger.kernel.org Subject: Re: RFC - how to balance Dirty+Writeback in the face of slow writeback. Message-ID: <20060818070314.GE798@suse.de> References: <17633.2524.95912.960672@cse.unsw.edu.au> <20060815010611.7dc08fb1.akpm@osdl.org> <20060815230050.GB51703024@melbourne.sgi.com> <17635.60378.733953.956807@cse.unsw.edu.au> <20060816231448.cc71fde7.akpm@osdl.org> <20060818001102.GW51703024@melbourne.sgi.com> <20060817232942.c35b1371.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060817232942.c35b1371.akpm@osdl.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 17 2006, Andrew Morton wrote: > It seems that the many-writers-to-different-disks workloads don't happen > very often. We know this because > > a) The 2.4 performance is utterly awful, and I never saw anybody > complain and Talk to some of the people that used DVD-RAM devices (or other excruciatingly slow writers) on their system, and they would disagree violently :-) It's been discussed here on lkml many times in the past, but that's years behind us now. Thankfully your pdflush work got rid of that embarassment. But it definitely does matter, to real ordinary users. -- Jens Axboe