On Wed, Mar 25, 2020 at 2:41 PM John wrote: > I can confirm that it is true with an encrypted ext4 partition. I get > the same error, "fstrim: /mnt/test: the discard operation is not > supported" when I try it there on the same device. Unless there is a > good reason for it, not having discard on LUKS encrypted partitions > seems like a pretty serious omission. Perhaps it is intentional.
I see now from searching that this is by design, https://wiki.archlinux.org/index.php/Dm-crypt/Specialties#Discard/TRIM_support_for_solid_state_drives_(SSD) I added the "discard" option to the entry in /etc/crypttab and rebooted. I am now able to get a successful run of fstrim on this F2FS partition: # fstrim -v /mnt/media /mnt/media: 0 B (0 bytes) trimmed Is it normal to return 0 bytes trimmed for F2FS partitions? By contrast, if I go to my test SSD, create a LUKS partition, open it with the --allow-discards option to cryptsetup, format it to ext4, mount that and then run fstrim on it, I am getting non-0 values for fstrim when I run it: # fstrim -v /mnt/test_crypt_ext4 /mnt/test_crypt_ext4: 3.9 GiB (4123463680 bytes) trimmed So I think something still isn't quite right with F2FS over crypto_LUKS. Thanks for the help! _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
