The Table of Disks

In many cases, disk data is most effectively viewed as a table. In this example, the disk statistics have been formatted into a table as well as text. Tables can be sorted by either percent busy or average service time, so that the most critical data is presented at the beginning of the table.

The -dtoo switch has been used to format disk statistics into the following table.

Disk Device Statistics
Disk Device	Average Percent Busy	Peak Percent Busy	Queue Depth When Occupied	Average Service Time
c0t6d0	2.39	16.0	2.2	20.3

The disk device c0t6d0 was busy an average of 2.39 percent of the time and had an average queue depth of 2.2 (when occupied). This indicates that the device is not a performance bottleneck. The average service time reported for this device and its accompanying disk subsystem was 20.3 milliseconds. This is somewhat slow for a modern disk drive, and the disappointing performance may be due to the disk or its controller. Service time is the delay between the time a request was sent to a device and the time that the device signaled completion of the request.