Proxmox5 Debian9 and iotop in container error

I have the same problem, iotop does not run in an LXC container (Container: Debain 9.9, Proxmox 6)

iotop version 0.6-2

Code:
root@lxc-container:~# iotop
Traceback (most recent call last):
  File "/usr/sbin/iotop", line 17, in <module>
    main()
  File "/usr/lib/python3/dist-packages/iotop/ui.py", line 620, in main
    main_loop()
  File "/usr/lib/python3/dist-packages/iotop/ui.py", line 610, in <lambda>
    main_loop = lambda: run_iotop(options)
  File "/usr/lib/python3/dist-packages/iotop/ui.py", line 508, in run_iotop
    return curses.wrapper(run_iotop_window, options)
  File "/usr/lib/python3.5/curses/__init__.py", line 94, in wrapper
    return func(stdscr, *args, **kwds)
  File "/usr/lib/python3/dist-packages/iotop/ui.py", line 498, in run_iotop_window
    taskstats_connection = TaskStatsNetlink(options)
  File "/usr/lib/python3/dist-packages/iotop/data.py", line 137, in __init__
    self.family_id = controller.get_family_id('TASKSTATS')
  File "/usr/lib/python3/dist-packages/iotop/genetlink.py", line 69, in get_family_id
    m = GeNlMessage.recv(self.conn)
  File "/usr/lib/python3/dist-packages/iotop/genetlink.py", line 51, in recv
    msg = conn.recv()
  File "/usr/lib/python3/dist-packages/iotop/netlink.py", line 229, in recv
    raise err
OSError: Netlink error: No such file or directory (2)

Then I took the Debian Buster version (0.6-24-g733f3f8-1) of it:
root@lxc-container:~# wget http://ftp.at.debian.org/debian/pool/main/i/iotop/iotop_0.6-24-g733f3f8-1_amd64.deb root@lxc-container:~# dpkg -i iotop_0.6-24-g733f3f8-1_amd64.deb

Code:
root@lxc-container:~/iotop-cgroups# iotop
Traceback (most recent call last):
  File "/usr/sbin/iotop", line 17, in <module>
    main()
  File "/usr/lib/python3/dist-packages/iotop/ui.py", line 737, in main
    main_loop()
  File "/usr/lib/python3/dist-packages/iotop/ui.py", line 727, in <lambda>
    main_loop = lambda: run_iotop(options)
  File "/usr/lib/python3/dist-packages/iotop/ui.py", line 620, in run_iotop
    return curses.wrapper(run_iotop_window, options)
  File "/usr/lib/python3.5/curses/__init__.py", line 94, in wrapper
    return func(stdscr, *args, **kwds)
  File "/usr/lib/python3/dist-packages/iotop/ui.py", line 609, in run_iotop_window
    taskstats_connection = TaskStatsNetlink(options)
  File "/usr/lib/python3/dist-packages/iotop/data.py", line 151, in __init__
    self.family_id = controller.get_family_id('TASKSTATS')
  File "/usr/lib/python3/dist-packages/iotop/genetlink.py", line 76, in get_family_id
    m = GeNlMessage.recv(self.conn)
  File "/usr/lib/python3/dist-packages/iotop/genetlink.py", line 56, in recv
    msg = conn.recv()
  File "/usr/lib/python3/dist-packages/iotop/netlink.py", line 255, in recv
    raise err
OSError: Netlink error: No such file or directory (2)

Still the same problem, so I found this forum post, I downloaded iotop for cgroups but I run into another problem:

./iotop.py -g -cgroups

CONFIG_TASK_DELAY_ACCT not enabled in kernel, cannot determine SWAPIN and IO %

On this blog ( http://blog.brocktice.com/2012/05/23/delayacct-and-iotop-in-ubuntu-10-04-lucid-lynx/ ) the solution proposed was to add delayacct to /etc/default/grub ( GRUB_CMDLINE_LINUX_DEFAULT="delayacct quiet" )

After a reboot the problem remained: CONFIG_TASK_DELAY_ACCT not enabled in kernel, cannot determine SWAPIN and IO %

So is there a way to run iotop in an LXC container or on the host with cgroups?
 
I found out that ./iotop.py -g /lxc/[CONTAINER-ID] is not enough to list just the container. You have to exactly put the string like shown in CGROUP when running just ./iotop.py (sort by CGROUP reversed). In my case it was:

Code:
./iotop.py -g /lxc/1234/ns