On Wed, 09 Jul 2008 08:48:42 +0200 Miklos Szeredi <miklos@xxxxxxxxxx> wrote: > On Tue, 8 Jul 2008, Arjan van de Ven wrote: > > nah he needs to do > > > > make_snapshot ; backup-command ; unref_snapshot. > > > > freezing isn't the right solution for the backup problem ;) > > Confused, what's freezing _is_ for then? Patch description says: > > Currently, ext3 in mainline Linux doesn't have the freeze feature > which suspends write requests. So, we cannot take a backup which > keeps the filesystem's consistency with the storage device's features > (snapshot and replication) while it is mounted. I tihnk the idea there is freeze . do the snapshot op . unfreeze . make backup of snapshot one can argue about the need of doing the first 3 steps via a userland loop; it sure sounds like one needs to be really careful to not do any writes to the fs from the app that does snapshots (and that includes doing any syscalls in the kernel that allocate memory.. just because that already could cause unrelated data to be written from inside the app. Not fun.) -- If you want to reach me at my work email, use arjan@xxxxxxxxxxxxxxx For development, discussion and tips for power savings, visit http://www.lesswatts.org -- 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
