From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from server.pyrenet.fr ([194.116.145.1]) by canuck.infradead.org with esmtp (Exim 4.43 #1 (Red Hat Linux)) id 1DdMiV-0000Up-IJ for linux-mtd@lists.infradead.org; Wed, 01 Jun 2005 02:28:41 -0400 Message-ID: <429D558E.5040706@perax.fr> Date: Wed, 01 Jun 2005 08:28:30 +0200 From: Ludovic Guilhamat MIME-Version: 1.0 To: manningc2@actrix.gen.nz References: <429C4D96.7000302@perax.fr> <20050601044012.1392D47AF@blood.actrix.co.nz> In-Reply-To: <20050601044012.1392D47AF@blood.actrix.co.nz> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit Cc: linux-mtd@lists.infradead.org, uClinux development list Subject: Re: Samsung RFS Filesystem List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Charles Manning a écrit : >On Tuesday 31 May 2005 23:42, Ludovic Guilhamat wrote: > > >>Hi, >> >>I would maybe interested in testing the Samsung RFS File System... >> >>Does someone, here, already used it, and what are the conclusions ? >> >> > > >Please do do some testing. It would be good to see the results, positive or >negative. > >I have not used it, but from a description I can draw some immediate >conclusions. > >RFS = Robust FAT file system > >>>From the blurb at >http://www.samsung.com/Products/Semiconductor/Flash/TechnicalInfo/rfs.htm > >this looks a bit like FATFS running on top of DOC. It might have some >transactioning which would make it look a bit more like Microsoft's TFAT. > >Neither of these are a proven reliable system. DOC can still get FAT >corruptions if you don't umount before power loss (== potentially a >completely scrambled fs). TFAT is completely unprovedn and is slower and not >always robust (not robust with typical mount options). Perhaps RFS gets the >robustness right. > > >Running FAT on NAND costs some performance due to the FTL etc. To make a >journaling system on FAT, as RFS claims, costs even more performance. > >IMHO: If you want robustnes on NAND use a log structured fs designed for >flash: YAFFS or JFFS2. > >For completeness, I will state that I wrote YAFFS, but I don't think this >biases my answer. > >-- CHarles > > > Thanks. Actually, the system I work on uses Jffs2 (Coldfire with uClinux). But, mount times are very long (the memory is a Flash Nand 16Mb). So, I planned to test Jffs2 patches (from the Jffs2 Improvement Project), then Yaffs. And as RFS is not freely distributed, and I don't know yet its cost, I wanted to know if someone had tested it. Thanks for your response. Ludovic.