From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shawn Rutledge Subject: Re: ReiserFS on a flash device? Date: Sat, 26 Jul 2003 17:03:01 -0700 Sender: Shawn Rutledge Message-ID: <20030727000301.GE894@ecloud.org> References: <200307261640.13629.swsnyder@insightbb.com> Mime-Version: 1.0 Return-path: list-help: list-unsubscribe: list-post: Errors-To: flx@namesys.com Content-Disposition: inline In-Reply-To: <200307261640.13629.swsnyder@insightbb.com> List-Id: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: reiserfs-list@namesys.com I wanted to use ReiserFS for an embedded system, but on a 32 or 64 meg CF card, v3 takes up too much of it for a journal, so it wasn't practical. Is there a way to make the journal much smaller, or have it grow on-demand rather than being fixed-size? In practice the CF card won't be written to very much (for longevity reasons), but I don't ever want an embedded system to waste time fscking itself and prompting what to do about any errors; and at the same time don't see why it should be required to be a read-only filesystem, as is often done, because it makes the occasional upgrade harder. And apparently JFFS2 is only for simple memory-mapped FLASH chips without built-in write-balancing like CF cards have. I use the mainstream ReiserFS in Linus' kernels on all my home machines and love it. It's so fast and stable as a rock, and the only problems I've had were hardware-related. On Sat, Jul 26, 2003 at 04:40:13PM -0700, Steve Snyder wrote: > I was taken aback by Yury Umanets' recent suggestion > (http://groups.google.com/groups?hl=en&lr=lang_en&ie=UTF-8&safe=off&th=d50aa0bf6c7f26d0&seekm=1059231274.28094.40.camel%40haron.namesys.com.lucky.linux.kernel#link11) > that ReiserFS is not an appropriate for a flash device. > > I am currently using it (via Linux kernel v2.4.21) on an E-Disk > (http://www.bitmicro.com/products_edisk_35_scsiw.php) flash device as the > front-end of a low-traffic Squid Web cache. The Squid experts recommend > the use of ReiserFS (with the notail option) for it's superior > performance in handling lots of small files. I understand that flash has > a finite number of write cycles, but for this application performance is > critical, and disk I/O (access times, not STR) is the bottleneck in Squid > performance. > > A quote from the post referred to above: > > >But, if you are still want to use reiserfs for flash device, you should > >do at least the following: > > > >(1) Make the journal substantial smaller of size. > >(2) Don't turn tails off. This is useful to prolong flash live. > > More detail, please? How is journal size a factor? How does notails > reduce flash longevity? > > Thanks. > > -- _______ Shawn T. Rutledge (_ | |_) e_cloud@yahoo.com * http://ecloud.org:8080 __) | | \________________________________________________________________