How is Disk IO calculated for Windows servers?

How is Disk IO calculated for Windows servers?

Here is how Disk IO calculation works:

We run diskio.vbs for getting DISK IO details. Here is a sample output:


diskio.vbs

Microsoft (R) Windows Script Host Version 5.8

Copyright (C) Microsoft Corporation. All rights reserved. 

PHYDISK^0 C: D: E: F:^0^13^13^0.016^0.562 

PHYDISK^1 J:^0^0^0^0.000^0


Busy time Calculation

IdleTime = (100 * (IdleTime2 - IdleTime1) / (TimeBase2 - TimeBase1))

Where IdleTime = Percentage of disk Idle time.

Busytime(%) = 100 - IdleTime(%)