On Friday 28 October 2011 23:11:22 Chris Tapp wrote:

Which is the 'best' filesystem to use for an embedded device that's
using a CF card?

It needs to survive loss-of-power, have a RO root filesystem, allow
user configuration data to persist and (ideally) only use 'Busybox'
commands.

This seems to imply the use of a partition for booting (mount RO) and
a second partition or a loop-device on the boot partition for
persistent storage.

I would normally go for ext3, but Busybox doesn't support it (afaik).
The Busybox tune2fs also only supports -L, so I can't stop 'disk needs
checking after <n> mounts' messages.

Is btrfs a suitable alternative?

Arnd Bergmann gave a talk at ELCE on flash drive performance (something he has
done quite a lot of research on); I did not attend but Darren and I spoke to
him later on, and if I recall correctly in his tests btrfs performed the best.
Hopefully the talk video will be available soon thanks to the folks at Free
Electrons; in the mean time there's an earlier article by Arnd on this topic
here:

http://lwn.net/Articles/428584/

Cheers,
Paul

--

Paul Eggleton
Intel Open Source Technology Centre