Messages in this thread |  | | | From | Chris Mason <> | | Subject | Re: BTRFS partition usage... | | Date | Tue, 12 Feb 2008 08:49:34 -0500 |
| |
On Tuesday 12 February 2008, David Miller wrote: > From: David Miller <davem@davemloft.net> > Date: Mon, 11 Feb 2008 23:21:39 -0800 (PST) > > > Filesystems like ext2 put their superblock 1 block into the partition > > in order to avoid overwriting disk labels and other uglies. UFS does > > this too, as do several others. One of the few exceptions I've been > > able to find is XFS. > > > > This is a real issue on sparc where the default sun disk labels > > created use an initial partition where block zero aliases the disk > > label. It took me a few iterations before I figured out why every > > btrfs make would zero out my disk label :-/ > > Actually it seems this is only a problem with mkfs.btrfs, it clears > out the first 64 4K chunks of the disk for whatever reason.
It is a good idea to remove supers from other filesystems. I also need to add zeroing at the end of the device as well.
Looks like I misread the e2fs zeroing code. It zeros the whole external log device, and I assumed it also zero'd out the start of the main FS.
So, if Btrfs starts zeroing at 1k, will that be acceptable for you?
-chris
|  |