Kofax Communication Server 9.1 User Manual

Page 39

Environment Guide

Version 3.00.04

or alternatively export the performance data from the VI client to the Excel sheet and consider afterwards:

Observe VI‟s counter CPU ready and CPU wait:

a.) CPU ready is the amount of time in ms (since last performance query

– 20 seconds by default) the VM

was ready to work but it was not scheduled by the ESX server. In other words, the higher CPU ready value

is, the fewer CPU resources the VM gets

b.) CPU wait is the time in ms the VM was scheduled by the ESX but did not have anything to do. In other

words, the higher CPU wait value is, the more CPU resources the VM gets even if it does not need them

The goal is to keep the CPU ready time low, refer to the example below:

a.) Up to ca. 18:15 the observed VM (with some granted CPU bandwidth) was idle, so the CPU ready time

was almost 0 (no activity in the VM) but the CPU wait time was very high (this time was effectively wasted

as the CPU time was allocated but no work to do)

b.) At about 18:15 the specific load was started, the CPU ready time increased a little but the CPU wait

time decreased substantially (it means that the CPU was used more effectively)

c.) At about 18:25 (during the load) the granted CPU bandwidth was removed from this VM: the CPU wait

decreases (the CPU is being used even more effectively), but the drawback is that the CPU ready time

increases (the application was more often ready to work but has to wait for the CPU)