In both Buster and Focal 20.11.1 on helios64 commands directed to a disk increment fields in /proc/diskstats
This is incorrect and does not occur in the x86 version of xubuntu Focal 20.04.1.
Specifically (see https://www.kernel.org/doc/Documentation/iostats.txt for field descriptions.):
Check Power Mode increments "number of reads completed"
Smart Return Status, Smart Read Data, and Smart Read Log increment "number of reads completed" and "number of sectors read"
The smartd disk monitor uses these commands which makes the disk appear to be active to programs like hd-idle.
The work-around is to set the inactive interval in hd-idle to something shorter (20 min, for example) than the polling interval of smartd (30 min default).
I would like to track this down but I need some help finding where these counters are incremented.
Is there a better place to report bugs like this than in this forum?
Thanks,
Jeff