The iostat utility has a rather unique method of interpreting command-line arguments. If no recognized disks are part of the command, it simply shows information about all of them. After devices, it checks for timing statistics. To get a second-by-second status, we specify one second as the final argument. By providing the -d argument, we remove CPU utilization from the report.
The default output rate of iostat is in kilobytes per second. Current hardware is often so fast that these results can be almost too high to easily compare, so we set the -m parameter in the second command to change the output to megabytes per second. We also take advantage of the fact that the last two parameters are related to timing. The first parameter ...
