There might be the odd occasion where you want to know what your drives are up to individually. Enter, dstat. Do follow the link as the site has a plethora of other options to try!
This tool is installable on Debian with apt install dstat and provides a bunch of useful information. You can run dstat on it's own and it will by default print information about disk total usage, net totals, paging information and system statistics. What we want though is to group drive writes for individual drives.
dstat -tdD total,sde,sdh,sdc 60For me, this produced the following output when left to run for one minute.
root@epsilon:/# dstat -tdD total,sde,sdh,sdc 60
----system---- -dsk/total----dsk/sde-----dsk/sdh-----dsk/sdc--
time | read writ: read writ: read writ: read writ
18-09 20:43:36| 17M 3423k:3078k 612k:4243k 821k: 527k 1565k
18-09 20:44:36| 62k 507k: 0 0 : 0 9694B: 62k 497kThere you have it. Quick and simple disk IO monitoring for Linux with dstat.