XFS, empty files after a crash

[Nathaniel W. Turner]

On 02/21/2012 10:18 PM, Eric Sandeen wrote:
> I'd agree that there is likely nothing to recover; there are no extents 
> allocated. I'm not sure why du is reporting space used though.

I have noticed that xfs_bmap (which uses the ioctl bmap interface) will not 
report extents after EOF.  There probably *are* extents allocated to this file, 
but they are not being reported by xfs_bmap.

kfx, try getting the inode number of the file (via stat or ls -i) and then 
doing something like this:

xfs_db -r $DEV -c "inode $INO" -c "bmap"

This will dump the entire extent map, and I suspect you'll see at least one extent.

nate