Hi. On Sat, Jul 17, 2021 at 02:03:15PM -0700, David Christensen wrote: > > But much more noticable is the difference of data reads of the two > > disks, i.e. 55 GB and 27 GB, i.e. roughly twice as much data is read > > from /dev/sdb compared to /dev/sda. Trying to figure out the reason > > for this, dmesg didn't give me anything > > Getting meaningful information from system monitoring tools is > non-trivial. Perhaps 'iostat 600' concurrent with a run of bonnie++. > Or, 'iostat 3600 24' during normal operations. Or, 'iostat' dumped to > a time-stamped output file run once an hour by a cron job.
iostat belongs to sysstat package. sysstat provides sar, which, by default, gathers every detail of the host resource utilization and a little more once per 10 minutes. There's little need for the kludges you're describing for one can simply invoke "sar -pd -f /var/log/sysstat/sa...". Reco