From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754068Ab1GLQU3 (ORCPT ); Tue, 12 Jul 2011 12:20:29 -0400 Received: from void.printf.net ([89.145.121.20]:49568 "EHLO void.printf.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753941Ab1GLQU1 convert rfc822-to-8bit (ORCPT ); Tue, 12 Jul 2011 12:20:27 -0400 From: Chris Ball To: Manoj Iyer Cc: linux-kernel@vger.kernel.org, jbarnes@virtuousgeek.org, matsumur@nts.ricoh.co.jp, linux-pci@vger.kernel.org, linux-mmc@vger.kernel.org Subject: Re: [PATCH] mmc: Added quirks for Ricoh 1180:e823 lower base clock frequency References: <1310419715-13254-1-git-send-email-manoj.iyer@canonical.com> <1310419715-13254-2-git-send-email-manoj.iyer@canonical.com> Date: Tue, 12 Jul 2011 12:20:17 -0400 In-Reply-To: (Manoj Iyer's message of "Tue, 12 Jul 2011 11:01:15 -0500 (CDT)") Message-ID: User-Agent: Gnus/5.110018 (No Gnus v0.18) Emacs/23.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Manoj, On Tue, Jul 12 2011, Manoj Iyer wrote: > Test System: ThinkPad X220 Tablet, using Sandisk 2GB Class 2 SD, I did > not see any considerable change in read/write times. Also, tested a > Transcend MMCPlus 2GB card, before the patch was applied it would not > mount the card, and would cause IO errors on read/write, but after the > patch it mounts and works correctly. > [..] > ============ BEFORE THE PATCH =============== > Sandisk 2GB Class2 SD > ============================================= > === WRITE === > u@u:~$ ls -lh test.file > -rw-r--r-- 1 u u 10M 2011-07-12 10:19 test.file > u@u:~$ time cp test.file /media/E0FD-1813/copyto > > real 0m0.480s > user 0m0.000s > sys 0m0.024s > [..] > ============ AFTER THE PATCH ============= > Sandisk 2GB Class2 SD > ========================================== > > === WRITE === > u@u:~$ time cp ./test.file /media/E0FD-1813/copyto1 > > real 0m0.757s > user 0m0.000s > sys 0m0.044s This suggests that there *was* a considerable difference in write speed, no? It might be helpful to use Arnd's flashbench tool¹ for further benchmarking, since it does the right thing with using direct I/O access without caches. Thanks, - Chris. ¹: http://git.linaro.org/gitweb?p=people/arnd/flashbench.git -- Chris Ball One Laptop Per Child