From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267576AbTHOQL4 (ORCPT ); Fri, 15 Aug 2003 12:11:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S270142AbTHOQL4 (ORCPT ); Fri, 15 Aug 2003 12:11:56 -0400 Received: from zeus.kernel.org ([204.152.189.113]:59269 "EHLO zeus.kernel.org") by vger.kernel.org with ESMTP id S267576AbTHOQI6 (ORCPT ); Fri, 15 Aug 2003 12:08:58 -0400 X-Originating-IP: [194.85.81.178] X-Originating-Email: [john_r_newbie@hotmail.com] From: "John Newbie" To: vda@port.imtp.ilyichevsk.odessa.ua Cc: linux-kernel@vger.kernel.org Subject: Re: ide drives performance issues, maybe related with buffer cache. Date: Fri, 15 Aug 2003 19:39:43 +0400 Mime-Version: 1.0 Content-Type: text/plain; format=flowed Message-ID: X-OriginalArrivalTime: 15 Aug 2003 15:39:43.0913 (UTC) FILETIME=[72F51990:01C36343] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > > So question is : why when i am copying file from one HD to another (for > > simplicity from /hda to /hdb) > > the speed fall down ? Starting from about 27-30 MB/s (drives are in >UDMA-4, > > hdparm -X68) it drops > > down to 11-12 MB/s after 4-5s. In *indows transfer rate is almost >constant > > and about 20-22 MB/s (same hardware). Why the h#ll we suck? > > I feel that it's due to buffer cache, because when you use sync (while > > copying) transfer rate is so small or even 0. > > Drives are tuned with hdparm to highest transfer rates, readahead, >multiple > > sector count (hdparm > > for details). > > Tried different filesystems, from classic ext2/3 to modern xfs/reiserfs. >The > > same results. > > Pure kernel from kernel.org (2.4.{19,20,21}), vendors kernels - all the >How do you copy files? cp? dd? Midnight Commander? ;) >Does it happen with SCSI? >-- >vda I've used cp & Midnight Commander (mc). Also when someone uploads big file on server through samba, speed sometimes fall down to zero. Have no idea about scsi, drives are IDE. _________________________________________________________________ Help STOP SPAM with the new MSN 8 and get 2 months FREE* http://join.msn.com/?page=features/junkmail