I would suggest just not writing them at all if you can avoid it. They seem to need (and are spec'd for) about 500ms of power after a write which isn't feasible with some power-off situations.

I've had them occasionally behave worse and develop "bad" sectors under what i thought to be normal operating conditions (meaning, I thought I satisfied the above limitation).

The bright side is that reclaiming "bad" sectors is just rewriting them, but if that's in the middle of something useful, like an inode for something in /lib, your superblock, the data portion of /etc/passwd, etc., you're in uncomfortable shape.

I would definitely advocate (and actively use them for) completely readonly disks, either by running completely readonly straight from the SanDisk or by keeping a (compressed?) readonly filesystem on the disk, booting readonly into a bootstrap environment, and copying or expanding a read/write root disk into a memory-based disk device (MD, MFS), and calling that your / partition. it's admittedly a rather klunky solution for a general purpose install.

It also makes putting /etc on non-volatile media difficult, but it is still workable with a bit of ingenuity, or maybe by using a small bootstrap /etc which is remounted with a stable vinum partition (I haven't actually tried this; implementation is left as an exercise for the reader).

Another consideration is that they have slow write performance relative to typical IDE or (especially) memory-based media.

- joel

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