Bedup crashes on ubuntu 18 after raid 1 rebalance

[leijurv]

mount: /tmp/tmpc851ykn1.privmnt: mount(2) system call failed: Cannot allocate memory.
Traceback (most recent call last):
  File "/home/leijurv/.local/bin/bedup", line 11, in <module>
    sys.exit(script_main())
  File "/home/leijurv/.local/lib/python3.6/site-packages/bedup/__main__.py", line 497, in script_main
    sys.exit(main(sys.argv))
  File "/home/leijurv/.local/lib/python3.6/site-packages/bedup/__main__.py", line 486, in main
    return args.action(args)
  File "/home/leijurv/.local/lib/python3.6/site-packages/bedup/__main__.py", line 127, in vol_cmd
    vols = whole_fs.load_all_writable_vols(tt)
  File "/home/leijurv/.local/lib/python3.6/site-packages/bedup/filesystem.py", line 567, in load_all_writable_vols
    loaded.extend(self.load_vols_for_fs(fs, tt))
  File "/home/leijurv/.local/lib/python3.6/site-packages/bedup/filesystem.py", line 537, in load_vols_for_fs
    fs.ensure_private_mpoint()
  File "/home/leijurv/.local/lib/python3.6/site-packages/bedup/filesystem.py", line 176, in ensure_private_mpoint
    + [str(self.uuid), pm])
  File "/usr/lib/python3.6/subprocess.py", line 291, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['mount', '-t', 'btrfs', '-o', 'subvol=/,noatime,noexec,nodev', '-nU', '7f6fa4a0-1892-4ac7-a232-18a9fadf355f', '/tmp/tmpc851ykn1.privmnt']' returned non-zero exit status 32.
Command exited with non-zero status 1