From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.ebshome.net (gate.ebshome.net [64.81.67.12]) (using TLSv1 with cipher EDH-RSA-DES-CBC3-SHA (168/168 bits)) (Client CN "gate.ebshome.net", Issuer "gate.ebshome.net" (not verified)) by ozlabs.org (Postfix) with ESMTP id A393F679F6 for ; Thu, 11 May 2006 02:48:12 +1000 (EST) Date: Wed, 10 May 2006 09:48:10 -0700 From: Eugene Surovegin To: Alex Zeffertt Subject: Re: Viable PPC platform? Message-ID: <20060510164810.GB32200@gate.ebshome.net> References: <20060509174101.389c67c0.ajz@cambridgebroadband.com> <20060509171520.GA10886@gate.ebshome.net> <20060510121141.0a866b8f.ajz@cambridgebroadband.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20060510121141.0a866b8f.ajz@cambridgebroadband.com> Cc: linuxppc-embedded@ozlabs.org, gd.smth@gmail.com List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, May 10, 2006 at 12:11:41PM +0100, Alex Zeffertt wrote: > On Tue, 9 May 2006 10:15:20 -0700 > Eugene Surovegin wrote: > > > On Tue, May 09, 2006 at 05:41:01PM +0100, Alex Zeffertt wrote: > > > On Tue, 09 May 2006 10:38:19 -0400 > > > geneSmith wrote: > > > > > > > I have a ppc405gpr system with 64M ram and 4Meg flash in a > > > > AM29LV320. Is this a viable platform for linux? Can a filesystem > > > > (JFFS2?) be put this flash type? > > > > > > > > > > I would create an initrd and put every file that doesn't need > > > to be changed persistently into it instead of JFFS2. > > > > After many years of doing embedded Linux stuff I still don't > > understand why people are so fond of initrd. > > > > For temporary stuff - tempfs is much better and flexible. For r/o > > stuff - just make separate MTD partition (cramfs, squashfs) and > > mount it directly as root. Both options will waste significantly > > less memory. > > > > Okay, let me qualify my answer. It depends on whether you need to > make persistent changes to the filesystem in flash. If so, and given > that your flash is only 4MB, I would recommend moving files to > somewhere else, e.g. an initrd, because if when a JFFS2 FS is > approaching full, you often find that writes to flash hang > while JFFS2 searches for blocks to use as a scratchpad. This has been > my experience anyway. > > If you don't need to make persistent changes to files, then I'm sure > cramfs in flash as a rootfs would work well, with a tmpfs partition > mounted on /tmp and /var. You missed my point. initrd should be stored somewhere - in the same flash . In this case there is no reason to actually use initrd instead of just direct mount from flash. -- Eugene