From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756649AbZCFSYm (ORCPT ); Fri, 6 Mar 2009 13:24:42 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753513AbZCFSY3 (ORCPT ); Fri, 6 Mar 2009 13:24:29 -0500 Received: from silver.sucs.swan.ac.uk ([137.44.10.1]:58110 "EHLO silver.sucs.swan.ac.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753320AbZCFSY2 (ORCPT ); Fri, 6 Mar 2009 13:24:28 -0500 Date: Fri, 6 Mar 2009 18:24:25 +0000 From: Sitsofe Wheeler To: Thanasis Cc: LKML Subject: Re: jffs2 and kernel config for SDHC Memory Cards Message-ID: <20090306182425.GB28349@silver.sucs.org> References: <49B127AB.6070202@asyr.hopto.org> <49B12B71.7030300@asyr.hopto.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <49B12B71.7030300@asyr.hopto.org> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 06, 2009 at 03:56:01PM +0200, Thanasis wrote: > on 03/06/2009 03:39 PM Thanasis wrote the following: > > I want to use two of these Transcend’s Class 6 SDHC (SD High-Capacity) > > Memory Cards, > > http://www.transcendusa.com/Products/ModDetail.asp?ModNo=147&LangNo=0&Func1No=1&Func2No=13 > > as part of the filesystem in a netbook (Acer A110L), will mount /home on > > one, and /tmp and /var on the other. > Let me rephrase my questions in order to be clearer: > Q1: In order to achieve wear leveling should I format them as jffs2? This probably won't be very effective as you are already past the anecdotal size recommended for jffs2 partitions (I've heard rumours that it is best suited to filesystems that are less than 64Mbytes and another that says less than 1Gbyte). Additionally you are not providing direct access to the raw flash (see http://linux-mtd.infradead.org/faq/jffs2.html#L_stick_jffs2 ). Performance is probably not gong to be very good. > Q2: In order to achieve wear leveling, any specific options I should > enable in kernel (2.6.28) configuration? You will be wear levelled by the hardware anyway as the hardware only provides a block device interface and you don't have access to the raw flash. ccing Dave Woodhouse as he is the JFFS2 creator. -- Sitsofe | http://sucs.org/~sits/