I'm now trying to port gopsutil to NetBSD, and there is a
IOCounters function to be ported, which is expected to fetch detailed io stats, like total reads/writes count/bytes, for each disks. It can be achieved by /proc/diskstats on Linux, and
hw.diskstats on OpenBSD. But I couldn't find a equivalent on NetBSD.
iostat looks promising but its outputs are quite limited and insufficient for this port need.