ESX shows VM using too much CPU

[kelv09]

I have two ESX 3.5 hosts clustered. ESX shows that my VM machines reach red alert very often. However, nothing is running in the VM that cause spike of CPU usage. Anyone can help me explain why?

Thanks,

[weinstein5]

What is the function of the VMs? Are they running anti-virus or back ups - both of these can cause temporary spikes?

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[kjb007]

Are the vmware tools installed?

-KjB

[kelv09]

One is using Windows 2003 - run Anti virus server and Windows Update Server. VMWare tools installed on this VM.

One Solaris- nothing on it yet. No VMware tools.

I check to see what Windows 2003 running that causes that spike in CPU...nothing at all. It pretty quiet so does Solaris.

Thanks,

[kjb007]

You should also your performance charts, as well as your alarms. I've seen false alerts from my alarms. Check to see the difference in time between the red alert for memory and the corresponding green alert in the tasks&events tab of the vm.

-KjB

[kelv09]

Trigger Type Condition Warning Alert

VM CPU Usage is above 75 90

Right now, the Windows VM using about 50% of CPU. However, I get a red alert. Is the alarms trustable? There were times it seems to work. Is there a way to correct this?

[kjb007]

You should adjust the alarm. By default, they are configured to alert, but not clear the alert right away. Edit the alarm definition, on the reporting tab, change the 0 in tolerance to something reasonable. 0 means that the status will never change. You will have to disable/renable the alarm to clear the alert.

-KjB