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On Tue, 30 Mar 2010 10:40:25 +0200 |
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Ingo Krabbe wrote: |
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|
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> On Mon, Mar 29, 2010 at 06:42:15PM -0400, David Relson wrote: |
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> > G'day, |
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> > |
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> > I'm porting the software for an embedded medical device from DOS to |
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> > Linux and am wondering which file systems are appropriate and which |
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> > are not. The device's mass storage is a Disk-on-Module solid state |
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> > flash drive. Data is presently written at approx 100 bytes every |
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> > 30 seconds but that might change to 100 bytes every second. The |
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> > device has a watchdog (recently activated) and during today's |
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> > session it was triggered and wiped out my file system. |
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> > |
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> > Anybody have recommendations on which file system to use and the |
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> > appropriate settings? |
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> > |
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> > Anybody have suggested readings so I can educate myself? |
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> |
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> First I would read about Wear Levelling (Wikipedia). Maybe your |
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> device already implements TrueFFS or ExtremeFFS with low-level wear |
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> levelling, so it might be enough to just use any other file system |
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> upon. Then I would choose a simple ext2 file system, though I can't |
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> tell the wear levelling really works. Are there methods to debug |
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> that? |
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> |
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> I think the best choose for you might be a JFFS2 Filesystem. Or just |
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> choose one from "Flash file system" in Wikipedia. |
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> |
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> bye ingo |
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|
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Hello Ingo, |
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|
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I've been using ext2 and have encountered some problems. In addition |
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to porting from DOS to Linux, the PC-104 board that has been used for |
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years has reached end-of-life, so there's a new PC-104 board that's |
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also involved. With the new board life has been good. With the old |
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board a file system problem has been encountered many times. |
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|
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For reasons totally unclear (at least to me), all of a sudden a file |
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can't be read or a shared library doesn't load. When I check using ls, |
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the message "Stale NFS file handle" appears. The device has _never_ |
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been on a network, so NFS doesn't actually play any role in the |
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device's life cycle. |
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|
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This has been happening at least a couple of times a week for the last |
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month. Often it happens several times in the same day. The file |
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handle problem has only happened with the old board, never with the |
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new. As there are several thousand "old board" devices in use, the |
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Linux port needs to support them. |
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|
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FWIW, the cpu is a 486 and we're using the 2.6.29.6 kernel. |
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|
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Regards, |
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|
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David |
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|
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P.S. The "flash file system" suggestion is appreciated! I'll check |
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into it. |
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