Fetching Extents takes a long time

[darthShadow]

Hi,

I have just started using fclones on a Ceph filesystem with 10M small files to dedupe and it looks like the extent fetching takes the longest time at 3+ hours.

[2023-09-23 21:51:46.677] fclones:  info: Started grouping
[2023-09-23 22:11:14.929] fclones:  info: Scanned 10923760 file entries
[2023-09-23 22:11:14.949] fclones:  info: Found 5185284 (606.8 GB) files matching selection criteria
[2023-09-23 22:11:17.219] fclones:  info: Found 4663625 (365.2 GB) candidates after grouping by size
[2023-09-23 22:11:19.740] fclones:  info: Found 4663625 (365.2 GB) candidates after grouping by paths
[2023-09-23 22:11:19.746] fclones: warn: File system ceph on device <device> doesn't support FIEMAP ioctl API. This is gener
[2023-09-24 01:49:42.109] fclones:  info: Found 1023608 (179.5 GB) candidates after grouping by prefix
[2023-09-24 01:49:42.818] fclones:  info: Found 1023608 (179.5 GB) candidates after grouping by suffix
[2023-09-24 02:36:13.630] fclones:  info: Found 1022246 (178.2 GB) redundant files

Is this something that can be cached for future runs, perhaps by the inode number?