From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp-out.bhp.t-online.de ([195.145.119.39]) by pentafluge.infradead.org with esmtp (Exim 4.14 #3 (Red Hat Linux)) id 19QwBi-00043I-F5 for ; Fri, 13 Jun 2003 22:34:22 +0100 Received: from ylva.bhp.t-online.de (ylva.ada.t-online.de [172.30.8.40]) 21 2002)) with SMTP id <0HGF00N6OVXB2I@smtp-out.bhp.t-online.de> for linux-mtd@lists.infradead.org; Fri, 13 Jun 2003 23:34:24 +0200 (MEST) Date: Sat, 14 Jun 2003 00:32:29 +0200 From: Thomas Gleixner In-reply-to: <1055484161.16455.133.camel@imladris.demon.co.uk> To: David Woodhouse , Chris Message-id: <200306140032.29488.tglx@linutronix.de> MIME-version: 1.0 Content-disposition: inline References: <1055484161.16455.133.camel@imladris.demon.co.uk> Content-type: text/plain; charset=iso-8859-15 Content-transfer-encoding: 7BIT cc: linux-mtd@lists.infradead.org Subject: Re: Reliability of NAND JFFS2 vs YAFFS for Embedded Systems Reply-To: tglx@linutronix.de List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Friday 13 June 2003 08:02, David Woodhouse wrote: > On Fri, 2003-06-13 at 01:05, Chris wrote: > > I am considering moving to the YAFFS filesystem due to reliablity > > concerns, but I am also wondering if YAFFS will have its own can of > > worms. I would like to have reliability, performance and space but > > reliability is the most important concern. > > > > Does anyone have experience with testing reliability of both > > configurations? > > If so what were the resutls? > > There's been powerfail testing done on JFFS2 on NOR; not yet for NAND > and there are some known corner cases which need sorting out before I > really undertake that. I have done intensive powerfail testing on NAND. I have no problem with JFFS2 and YAFFS. I think both are reliable and have their (dis)advantages. Both filesystems have invalid files on it, if the powerfail occures during a file write. That's normal behaviour. This would be the same on your harddisk or any other medium. I have never seen a serious fs corruption neither on JFFS2 nor on YAFFS, except for some development phases, when the code was buggy. That's normal for work in progress too. The only unsolved problem for JFFS2 on NAND at the moment is a writebuffer flush failure. This has hit me once during a log term test, where a sector went bad after > 1.200.000 erase cycles. But this did not corrupt the hole filesystem. It was just the last written file, which was lost. It should be not too hard to fix that at least, if somebody has enough time or someone does a little sponsoring for that :) -- Thomas ________________________________________________________________________ linutronix - competence in embedded & realtime linux http://www.linutronix.de mail: tglx@linutronix.de