Ensure that btfs has mounted data

[emanaev]

Seems like you need to analyze btfs logs (gathered with btfs -f -d ):

FUSE library version: 2.9.4
nullpath_ok: 0
nopath: 0
utime_omit_ok: 0
unique: 1, opcode: INIT (26), nodeid: 0, insize: 56, pid: 0
INIT: 7.23
flags=0x0003fffb
max_readahead=0x00020000
   INIT: 7.19
   flags=0x00000011
   max_readahead=0x00020000
   max_write=0x00020000
   max_background=0
   congestion_threshold=0
   unique: 1, success, outsize: 40
Got metadata. Now ready to start downloading.
handle_piece_finished_alert: 779
handle_piece_finished_alert: 1269
handle_piece_finished_alert: 1365
handle_piece_finished_alert: 1431
handle_piece_finished_alert: 1487
handle_piece_finished_alert: 2
handle_piece_finished_alert: 15
handle_piece_finished_alert: 6
handle_piece_finished_alert: 3
handle_piece_finished_alert: 5
handle_piece_finished_alert: 11
handle_piece_finished_alert: 12
handle_piece_finished_alert: 13
handle_piece_finished_alert: 7