Mismatch in IO from header vs table when running with -a option

[graysky2]

Running iotop -a as root is showing plenty of disk read in the header section, yet nothing is getting recorded in the "Disk Read" column:

  Total DISK READ:   53.00 M   ⣿⣿⣿⣿⣿⣿⣷⣶⣶⣶⣶⣶⣦⣤⣤ |   Total DISK WRITE:   36.00 K   ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿
Current DISK READ: 1005.89 K/s ⣶⣶⣷⣶⣾⣶⣶⣷⣶⣾⣶⣶⣷⣶⣷ | Current DISK WRITE:    0.00 B/s ⠀⠀⠀⠀⠀⠀⠀⠀⠀⡀⠀⠀⡇⠀⠀
TID     PRIO USER      DISK READ▽  DISK WRITE  SWAPIN   IO       GRAPH[IO]       COMMAND                              (08:48:45)
    1   be/4 root         0.00 B      0.00 B     0.00 %   0.00 % ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀  systemd                                      ▲
    2   be/4 root         0.00 B      0.00 B     0.00 %   0.00 % ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀  kthreadd                                     █
    3   be/4 root         0.00 B      0.00 B     0.00 %   0.00 % ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀  pool_workqueue_release                       █
    4   be/0 root         0.00 B      0.00 B     0.00 %   0.00 % ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀  kworker/R-rcu_gp                             ▁
    5   be/0 root         0.00 B      0.00 B     0.00 %   0.00 % ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀  kworker/R-sync_wq
...

Am I invoking the program incorrectly?

[bbonev]

Most probably you are not running it in an incorrect way...

Which version is that? Does the same happen with 1.30 or latest git?

[graysky2]

This is version 1.30 on Arch Linux.

[unknown-spirit]

I could replicate the problem on Manjaro 25 and I think it directly relates to #87 issue.
In fact, disk read does appear in the list, but far below (after some 0.00 entries).
So you either scroll down a bit or press "p" to deactivate threads' display.