On 2020/3/24 4:12, John wrote: > On Mon, Mar 23, 2020 at 11:02 AM Jaegeuk Kim <jaeg...@kernel.org> wrote: >>> /dev/mapper/media-crypt /mnt/media f2fs >>> rw,lazytime,relatime,background_gc=on,discard,no_heap,user_xattr,inline_xattr,acl,inline_data,inline_dentry,flush_merge,extent_cache,mode=adaptive,active_logs=6,alloc_mode=default,fsync_mode=posix >> >> - media-crypt means dm-crypt? Any chance to try raw sda? > > Yes, it is dm-crypt. > >> Could you try this? >> - mount -o remount,nodiscard >> : The reason is, as f2fs uses async discard feature with -o discard, it >> doesn't >> give 0 bytes on fstrim sometimes. > > I can confirm it is mounted now with the nodiscard option, but fstrim > still claims discard is not supported.
Can you try below command and show us the result to see whether device supports discard: strace blkdiscard -o 0 -l 4096 /dev/mapper/media-crypt It may discard first 4k block which is first superblock of f2fs, for safety, it will be better to backup all your data before executing the command. Thanks, > > % mount | grep crypt > /dev/mapper/media-crypt on /mnt/media type f2fs > (rw,relatime,lazytime,background_gc=on,nodiscard,no_heap,user_xattr,inline_xattr,acl,inline_data,inline_dentry,flush_merge,extent_cache,mode=adaptive,active_logs=6,alloc_mode=default,fsync_mode=posix,x-systemd.automount) > > # fstrim -v /mnt/media > fstrim: /mnt/media: the discard operation is not supported > . > _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
