Read IO stats from iostat if /proc/diskstats is empty

[thijsc]

In LXC containers it seems like /proc/diskstats is empty, while iostats does give relevant information. iostats is not available everywhere. Maybe fall back on it if /proc/diskstats is empty?

[tombruijn]

We should probably search this in the /sys/fs/ directory instead.

[vbmade2000]

is iostats external utility ? I checked in my Ubuntu 20 but didn't find it.

[tombruijn]

@vbmade2000 yes I think it's an external utility and it's not installed by default.