Posted Jan 27, 2006 0:16 UTC (Fri) by drag
In reply to: snapshots?
Parent article: MD / DM
There is those "log-structure" filesystems. There are a couple currently in the works for Linux.. one from a telecom company from Japan and another one that made it into that 'google summer of code'.
They write like a log were you start at the beginning of the disk and just walk down the drive never overwriting old data or zeroing anything out.
You get undelete features, the ability to mount a snapshot of the file system at any time in it's history while the real volume is still online, access a file at any time during it's history. That sort of thing. Also has other advantages like very fast write speeds and robustness against loosing data.. even in a file system corruption. (if stuff gets added to the end of a file, just rollback the changes till you get to good data)
Of course it's got problems.. intense file system fragmentation and difficulty with figuring out the best way to reclaim and reuse disk space. It wouldn't be good for general purpose stuff.
to post comments)