Re: [gentoo-embedded] file system question

[Ingo Krabbe <ikrabbe.ask@web.de>]

On Mon, Mar 29, 2010 at 06:42:15PM -0400, David Relson wrote:
> G'day,
> 
> I'm porting the software for an embedded medical device from DOS to
> Linux and am wondering which file systems are appropriate and which are
> not.  The device's mass storage is a Disk-on-Module solid state flash
> drive.  Data is presently written at approx 100 bytes every 30 seconds
> but that might change to 100 bytes every second.  The device has a
> watchdog (recently activated) and during today's session it was
> triggered and wiped out my file system.
> 
> Anybody have recommendations on which file system to use and the
> appropriate settings?
> 
> Anybody have suggested readings so I can educate myself?

First I would read about Wear Levelling (Wikipedia).  Maybe your device already
implements TrueFFS or ExtremeFFS with low-level wear levelling, so it might be
enough to just use any other file system upon.  Then I would choose a simple
ext2 file system, though I can't tell the wear levelling really works.  Are
there methods to debug that?

I think the best choose for you might be a JFFS2 Filesystem.  Or just choose one
from "Flash file system" in Wikipedia.

bye ingo