I'm running Debian Testing with kernel 5.2.17-1. Five disk raid1 with at least 393.01GiB unallocated on each disk. No device errors. No kernel WARNINGs or ERRORs.
BTRFS info (device dm-1): enabling auto defrag BTRFS info (device dm-1): using free space tree BTRFS info (device dm-1): has skinny extents Mounted with noauto,noatime,autodefrag,skip_balance,space_cache=v2,enospc_debug. First btrfs_dump_space_info() is BTRFS info (device dm-1): space_info 4 has 18446744073353838592 free, is not full BTRFS info (device dm-1): space_info total=10737418240, used=9636544512, pinned=0, reserved=27066368, may_use=1429454848, readonly=65536 BTRFS info (device dm-1): global_block_rsv: size 536870912 reserved 536870912 BTRFS info (device dm-1): trans_block_rsv: size 0 reserved 0 BTRFS info (device dm-1): chunk_block_rsv: size 0 reserved 0 BTRFS info (device dm-1): delayed_block_rsv: size 20185088 reserved 20185088 BTRFS info (device dm-1): delayed_refs_rsv: size 868745216 reserved 868745216 and current last is BTRFS info (device dm-1): space_info 4 has 0 free, is not full BTRFS info (device dm-1): space_info total=10737418240, used=9664561152, pinned=458752, reserved=2523136, may_use=1069809664, readonly=65536 BTRFS info (device dm-1): global_block_rsv: size 536870912 reserved 536821760 BTRFS info (device dm-1): trans_block_rsv: size 0 reserved 0 BTRFS info (device dm-1): chunk_block_rsv: size 0 reserved 0 BTRFS info (device dm-1): delayed_block_rsv: size 0 reserved 0 BTRFS info (device dm-1): delayed_refs_rsv: size 556531712 reserved 498647040 with lots more in between and no other Btrfs kernel printing preceding it since mounting. It's the first time I'm seeing it but I have always mounted with enospc_debug since it always seems too late to add the option when you finally need it. What does it mean? Should I be worried? What to do? No apparent problems yet.
