On Oct 29, 2010, at 9:21 AM, Jesus Cea wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > Hi, everybody. > > I have a question about the inner working of ZFS. Hope somebody can > provide some light. > > ZFS keeps 128 uberblocks around, just in case the last transactions are > corrupted for any reason. > > My question is about block freeing. > > When a file is deleted, its block are freed, and that situation is > committed in the next txg. Fine. Now those blocks are free, and can be > used in new block requests. Now new requests come and the (now free) > blocks are reused for new data.
ZFS will not reuse blocks for 3 transaction groups. This is why uberblock rollback will do normally only attempt a rollback of up to two previous txgs. - Eric -- Eric Schrock, Fishworks http://blogs.sun.com/eschrock _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
