This week I was visiting a client who bought an expansion on their MD3000i storage of 5 disks.
I wanted to know if all 6 servers would fit on a new raid 5 set (4+1) so I started to monitor the Disk Commands/Sec with ESXTOP for a number of hours to see what the servers generate on a normal working day with everybody at work.
I logged in both ESX hosts and started ESXTOP
Make sure you only capture relevant info.
You need to remove all all other fields in c:cpu i:interrupt m:memory n:network d:disk adapter u:disk device p:power
remove (f) the metrics you don’t need. After that write (w) the configuration to disk to /tmp/io
this example uses v:disk metric
Enter command: “esxtop -b -c /tmp/io -d 2 -n 5400 > /tmp/diskio-pervm.csv”
- -b is for batch mode
- -c is the configfile for esxtop which you saved.
- -d sets the delay between updates in seconds.
- -n runs esxtop for only n iterations, in this case 30 times per minute x 60 times per hour x 3 hours = 5400
- /tmp/diskio-pervm.csv is the location where the output of the logging will be written.