After running xfs_db to check fragmentation of one of our file system /dev/sda4 it showed 70.8% fragmentation. Due to production we could not run the xfs_fsr and reboot the server until a few day later. Prior to executing xfs_fsr on /dev/sda4, I rechecked it with xfs_db and it showed only 12.5%. I know the system wasn't rebooted and that no one else executed a defragmentation. Is it possible that this is result of files that were heavily fragmented having been deleted?

Also, it seems that it is necessary to reboot to see the affects of xfs_fsr, is there any other way?