Linux systems provide a handy suite of commands for helping you see how busy your disks are, not just how full. In this post, we examine five very useful commands for looking into disk activity. Two of the commands (iostat and ioping) may have to be added to your system, and these same two commands require you to use sudo privileges, but all five commands provide useful ways to view disk activity.
Probably one of the easiest and most obvious of these commands is dstat.
In spite of the fact that the dstat command begins with the letter “d”, it provides stats on a lot more than just disk activity. If you want to view just disk activity, you can use the -d option. As shown below, you’ll get a continuous list of disk read/write measurements until you stop the display with a ^c. Note that after the first report, each subsequent row in the display will report disk activity in the following time interval, and the default is only one second.
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