Step 1: Verify the available disks
$ lsblk
Step 2: With top command make sure if there CPU is waiting.
Step 3: iostat -xyh 1 3
x => extended output
y => Igonored first output
h => human readable
1 => every 1 second print output
3 => for 3 times
x => extended output
y => Igonored first output
h => human readable
1 => every 1 second print output
3 => for 3 times
This doesn't help in identifying which process is actually causing the IO Wait. For this scenario to know about which process actually causing we need to use "iotop" which is in most case not installed by default.
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