Paul P Komkoff Jr wrote:
Replying to David Woodhouse:
>RAID is just a hack which hides the redundancy from the file system; the
>kind of thing we always used to have to do for DOS compatibility so that
>we could provide an INT 13h handler and have it 'just work'. It's much
>the same reasoning which led to the built-in 'translation layers' on
>cheap CF cards and USB sticks which so often eat your data and which
>have a tendency to use up their limited lifetime in copying obsolete
>sectors belonging to deleted files around on the underlying medium.
>
>We don't _need_ that kind of layering in Linux. Have a library of
>functions which can be used for such redundancy, by all means -- but
>don't just make RAID pretend to be a 'standard' block device and prevent
>all possibility of sharing knowledge between the file system and the
>layer providing the redundancy. That's just insane.
>
>
Well, everything you said habove is correct. But I've yet seen any
"redundant block device filesystem" project anywhere.
Sun zfs, Isilon OneFS, possibly others.
--
Do not meddle in the internals of kernels, for they are subtle and quick to panic.