For example, /mnt/fs1 has file1 of size 40KB Do a reflink cp of /mnt/fs1 to /mnt/.snap/1 Now, when I check the size of /mnt/.snap/1/, it should show only snap usage. In this case, it should be 0, as no blocks are unique to this snap. Modify file1 in /mnt/fs1, modify 2 blocks of block size 4 KB. Take snapshot /mnt/snap/2 --.> This should show only the unique snap usage as 8KB. I understand there is no snap accounting in XFS. However, to achieve the above things, is there any XFS command that can help? Thanks in advance for your time. On Mon, Jul 14, 2025 at 11:28 AM Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: > > On Sat, Jul 12, 2025 at 01:19:19PM +0530, Priya PM wrote: > > Hi, > > > > I was using reflinks to create snapshots of an XFS filesystem; > > however, I’m looking for ways to determine the unique snapshot usage > > or perform snapshot accounting. > > Can you explain what you are trying to measure? How many blocks in a > given file are refcounted blocks with other users? Or the difference > between i_blocks for all files combined vs actual space usage? > > There isn't really such a thing as snapshot accouting in XFS. >
