The filesystem has become very, very slow. smartctl doesn't show any problems with the HDD. My usual btrfs maintenance (balance, scrub, defrag) did not show any problems -- but did not resolve the slowness. So I ran a btrfs check -- the result is pasted below. What causes this and is there any solution other than recreating the file system? Would the errors shown below make a btrfs filesystem slow?
Opening filesystem to check... Checking filesystem on /dev/mapper/bak_luks UUID: 3ac770bc-e7c4-4792-2d2d-1d3ed19d126b [1/7] checking root items [2/7] checking extents ref mismatch on [374849568768 16384] extent item 0, found 1 tree backref 374849568768 parent 6835 root 6835 not found in extent tree backpointer mismatch on [374849568768 16384] owner ref check failed [374849568768 16384] ref mismatch on [374940549120 16384] extent item 0, found 1 tree backref 374940549120 parent 6835 root 6835 not found in extent tree backpointer mismatch on [374940549120 16384] owner ref check failed [374940549120 16384] ref mismatch on [569319473152 16384] extent item 0, found 1 tree backref 569319473152 parent 6835 root 6835 not found in extent tree backpointer mismatch on [569319473152 16384] ref mismatch on [569329385472 16384] extent item 0, found 1 tree backref 569329385472 parent 6835 root 6835 not found in extent tree backpointer mismatch on [569329385472 16384] ref mismatch on [569516376064 16384] extent item 0, found 1 tree backref 569516376064 parent 6835 root 6835 not found in extent tree backpointer mismatch on [569516376064 16384] ref mismatch on [570749665280 16384] extent item 0, found 1 tree backref 570749665280 parent 6835 root 6835 not found in extent tree backpointer mismatch on [570749665280 16384] ERROR: errors found in extent allocation tree or chunk allocation [3/7] checking free space cache [4/7] checking fs roots [5/7] checking only csums items (without verifying data) [6/7] checking root refs [7/7] checking quota groups skipped (not enabled on this FS) found 3655790232414 bytes used, error(s) found total csum bytes: 3534402188 total tree bytes: 46277705728 total fs tree bytes: 34533392384 total extent tree bytes: 7925743616 btree space waste bytes: 8021706864 file data blocks allocated: 30545889550336 referenced 31161532510208
