STEP 2. Monitoring Disks
If you’ve made it to Step 2, then you know by now exactly what is going on with memory on your system. The next step is to find out whether you have any disk bottlenecks or disks that may soon become bottlenecks.
Use iostat, statit, or sar to check for a disk bottleneck. The statit utility is available on the book website.
Try iostat -xn 5 (the -n option, which displays disk names in the c n tn d n format, is only available from Solaris 2.6 on). If you have a lot of disks, you may be so overwhelmed by the output that you find it hard to make sense of all that data. You can use grep to remove idle disks from the display (after asking yourself why you have idle disks!):
iostat -xn 5 | grep -v “0.0 0.0 0.0 0.0 0.0 0.0 ...