Hi! > Actually, there is something the file system can do to make journaling > safe on degraded RAIDs: make the (checksummed) journal blocks equal to > the RAID stripe size. Or, equivalently, pad out to the RAID stripe > size each commit. > > This sometimes leads to awkward block sizes, but while writing > to any *one* stripe on a degraded RAID-5 endangers the others, you > can write to *all* of them with the usual semantics. Well, that would work... but you'd also have to journal data, with the same block size. Not exactly fast, but at least safe... > That's one thing I really like about ZFS: its policy of "don't trust > the disks." If nothing else, simply telling you "your disks f*ed up, > and I caught them doing it", instead of the usual mysterious corruption > detectec three months later, is tremendoudly useful information. The more I learn about storage, the more I like idea of zfs. Given the subtle issues between filesystem and raid layer, integrating them just makes sense. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
