Interpreting ready on host object

[gatsby23]

Hello -

This is probably a pretty basic question: I have a decent understanding of how CPU ready plays into things at the virtual machine level, but when I look at the performance graph for my ESXi host (with the CPU usage and Ready counters), I am surprised to see Ready has any value attached to it at all. For example, if my physical host CPU usage is recorded as 14%, the corresponding Ready value is 109,195 ms. My CPU usage is not high, so I am wondering why Ready is registering for my host, or whether it means something different on host objects as opposed to virtual machine objects. Thanks for any insight.

[DavoudTeimouri]

Hi,

You know, the %READY field for the percentage of time that the virtual machine was ready but could not be scheduled to run on a physical CPU.

For check it deeply, use ESXTOP on your hosts or Visual ESXTOP (available on VMware Lab). I think, host CPU ready is not matter and you should check it on your VMs.

The metric is depended to your VM CPU Usage, its core numbers, VM numbers and your host workload.

Many useful articles are available on Internet about that.

[Wh33ly]

gatsby23 wrote:

Hello -

This is probably a pretty basic question: I have a decent understanding of how CPU ready plays into things at the virtual machine level, but when I look at the performance graph for my ESXi host (with the CPU usage and Ready counters), I am surprised to see Ready has any value attached to it at all. For example, if my physical host CPU usage is recorded as 14%, the corresponding Ready value is 109,195 ms. My CPU usage is not high, so I am wondering why Ready is registering for my host, or whether it means something different on host objects as opposed to virtual machine objects. Thanks for any insight.

CPU Ready time in performance chart is in milliseconds, not in percentage.

Depending on the view (VM or per vCPU) it is the amount of time in ms how long it takes before the workload is scheduled. Also depending on the view (realtime/past day/week/year) the numbers will increase. For a good understanding about this I would like to refer you to post:

http://vmtoday.com/2013/01/cpu-ready-revisted-quick-reference-charts/

It gives a good understanding how it is calculated and interpret the results.

Hope this will answer your question a bit

[lvaibhavt]

Did you get a chance to check all the VMs on the host have high Ready time or it looks normal on them ?