From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753595AbXCZKIh (ORCPT ); Mon, 26 Mar 2007 06:08:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753593AbXCZKIh (ORCPT ); Mon, 26 Mar 2007 06:08:37 -0400 Received: from smtp.osdl.org ([65.172.181.24]:51314 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753595AbXCZKIf (ORCPT ); Mon, 26 Mar 2007 06:08:35 -0400 Date: Mon, 26 Mar 2007 02:08:23 -0800 From: Andrew Morton To: Miklos Szeredi Cc: dgc@sgi.com, linux-kernel@vger.kernel.org Subject: Re: [patch 1/3] fix illogical behavior in balance_dirty_pages() Message-Id: <20070326020823.8630bb07.akpm@linux-foundation.org> In-Reply-To: References: <20070325153508.10922ebd.akpm@linux-foundation.org> <20070326010124.b4513ce2.akpm@linux-foundation.org> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.17; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 26 Mar 2007 11:32:47 +0200 Miklos Szeredi wrote: > Stopping writers which have idle queues is completely unproductive, > and that is basically what the current algorithm does. This is because the kernel permits all of its allotment of dirty+writeback pages to be dirty+writeback against a single device. A good way of solving the one-device-starves-another-one problem is to dynamically adjust the per-device dirty+writeback levels so that (for example) if two devices are being written to, each gets 50% of the allotment. I started working on that but got derailed by the usual blah. I don't think either of the proposed fixes took that approach, actually.