I'm replacing a failed harddrive in a mirrored btrfs.btrfs device delete missing /[mountpoint] is taking very long, so I assume that it's actually rebalancing data across to the replacement drive.Is there any way to monitor the progress of such an operation?I don't necessarily expect a pretty looking GUI, or even a % counter; and I'm willing to write a couple of lines of shell script if that's necessary, but I don't even know where to start looking for relevant data. btrfs filesystem show for example just hangs, presumably waiting for the balance operation to finish before it displays any information about the mirrored fs.
Is there a way to monitor progress of a btrfs rebalance?
btrfs
btrfs balance status /mountpointman 8 btrfs [filesystem] balance status [-v] <path>        Show status of running or paused balance.        Options        -v   be verbose