Missing columns on larger collections with iostat #396

Hello, with sysstat version 12.6.1 while using iostat with the json output i am seeing an issue where it sometimes "loses" a few fields for the disk statistics.

in this image we can see this with sdu.

This seems to happen very randomly and inconsistently but often enough to where it causes issues for my testing infrastructure.

I run this usually for 60 seconds with 1 second intervals.
The machines tend to have a considerable amount of drives.

This is how i usually run the command:

iostat -dtx -p ALL -o JSON 1 60 > some_filename.json

Any help or insight would be appreciated. Please let me know if there is any information I can provide that could help.

Thanks

EDIT: using kernel 6.6.29