Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 27 Dec 2000 16:22:58 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 27 Dec 2000 16:22:38 -0500 Received: from d185fcbd7.rochester.rr.com ([24.95.203.215]:41994 "EHLO d185fcbd7.rochester.rr.com") by vger.kernel.org with ESMTP id ; Wed, 27 Dec 2000 16:22:31 -0500 Date: Wed, 27 Dec 2000 15:49:20 -0500 From: Chris Mason To: Daniel Phillips , linux-kernel@vger.kernel.org Subject: Re: [RFC] changes to buffer.c (was Test12 ll_rw_block error) Message-ID: <18670000.977950159@coffee> In-Reply-To: <3A4A505A.3CF8A8BB@innominate.de> X-Mailer: Mulberry/2.0.6b1 (Linux/x86) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday, December 27, 2000 21:26:02 +0100 Daniel Phillips wrote: > Hi Chris. I took your patch for a test drive under dbench and it seems > impressively stable under load, but there are performance problems. > > Test machine: 64 meg, 500 Mhz K6, IDE, Ext2, Blocksize=4K > Without patch: 9.5 MB/sec, 11 min 6 secs > With patch: 3.12 MB/sec, 33 min 51 sec > Cool, thanks for the testing. Which benchmark are you using? bonnie and dbench don't show any changes on my scsi disks, I'll give IDE a try as well. > Philosophically, I wonder if it's right for the buffer flush mechanism > to be calling into the filesystem. It seems like the buffer lists > should stay sitting between the filesystem and the block layer, it > actually does a pretty good job. > What I'm looking for is a separation of the write management (aging, memory pressure, etc, etc) from the actual write method. The lists (VM, buffer.c, whatever) should do the management, and the FS should do the i/o. This patch is not a perfect solution by any means, but its a start. -chris - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/