From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965046AbVIALtn (ORCPT ); Thu, 1 Sep 2005 07:49:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965088AbVIALtn (ORCPT ); Thu, 1 Sep 2005 07:49:43 -0400 Received: from pilet.ens-lyon.fr ([140.77.167.16]:32164 "EHLO relaissmtp.ens-lyon.fr") by vger.kernel.org with ESMTP id S965046AbVIALtn (ORCPT ); Thu, 1 Sep 2005 07:49:43 -0400 Message-ID: <4316EAD1.70300@ens-lyon.org> Date: Thu, 01 Sep 2005 13:49:37 +0200 From: Brice Goglin User-Agent: Mozilla Thunderbird 1.0.2 (X11/20050602) X-Accept-Language: fr, en MIME-Version: 1.0 To: DervishD Cc: Linux-kernel Subject: Re: USB Storage speed regression since 2.6.12 References: <20050901113614.GA63@DervishD> In-Reply-To: <20050901113614.GA63@DervishD> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Le 01.09.2005 13:36, DervishD a écrit : > I don't know if this is a known issue, but usb-storage speed for > 'Full speed' devices dropped from 2.6.11.12 (more than 800Kb/s) to > 2.6.12 (less than 250Kb/s). The problem still exists in 2.6.13. > > The lack of speed seems to affect only the OHCI driver. My test > was done over a PCI USB 2.0 card, ALi chipset, OHCI driver (well > EHCI+OHCI) and using a full speed device capable of 12MBps. The > average measured speeds are: > > - 2.4.31: about 450Kb/seg > - 2.6.11-Debian: about 800Kb/seg > - 2.6.11.12: about 820Kb/seg > - 2.6.12.x: about 200Kb/seg > - 2.6.13: about 200Kb/seg Are you mounting this storage with vfat and 'sync' option ? IIRC, sync support for vfat was added around 2.6.12, making write way slower since it's now really synchron. Brice