VM "bad performance" but CPU usage and Memory usage are OK!

[VCPGuru]

A colleague told me that his VM performances bad. I checked in vCenter the CPU Usage (Maximum over last month) and Memory Usage (Maximum over last month) both values are below 75%.

CPU ready value (over last week maximum) was 83968.

The VM has 1vCPU and 4GB RAM

What should I do???

Any help would be appreciated

[Chuck8773]

That is a very high CPU ready value. Log into the host and use ESXTOP to find what else is contending with the CPU.

How many VM's are on this host? How large is the host in terms of CPU and RAM? What type of disk subsystem does the ESX host use? SATA? SAS? RAID 5? RAID50? RAID 10? How many disks in the RAID set?

Charles Killmer, VCP

If you found this or other information useful, please consider awarding points for "Correct" or "Helpful".

[RParker]

What should I do???

We need LOTS more info..

Is this a P2V, is it Windows (what version) ?, what processes are running, has the VM been configured for VM efficiency (remove uncessary drivers, turn off services not being used, etc...). What is the VM for, are the programs certified for VM's..

blah blah blah.. There is more than just sticking an OS in a VM we have to know details. A VM in and of itself isn't the problem.

[VCPGuru]

No P2V

Windows 2008 Std

Certified for VMware

Latest VMware Tools are installed

ESX Host 32GB Memory / 8 Cores --> 14 VMs (Average VM with 2Cores/ 2048MB Memory)

[Scissor]

ESX Host 32GB Memory / 8 Cores --> 14 VMs (Average VM with 2Cores/ 2048MB Memory)

It is harder for ESX to schedule Guests that are configured with more than 1 vCPU. Can you convert more of your Guests to 1 vCPU? I'll bet that will resolve your problems.

[J1mbo]

28 vCPU to 8 cores seems quite a high ratio as well, if the overall server load if 75%.

[VCPGuru]

The ESX host CPU consumation value is under 30% so I think I should deploy VMs unti I have an average CPU usage of the host of 60%. What is year meaning? Best Practice Values?

[Chuck8773 · Accepted solution]

If you overcommit the CPU that far, you will have contention on the CPU's. We keep our cluster around 25% CPU usage on average. We won't push it any higher in 3.5. V4 may allow a higher value, but that remains to be tested.

Try reducing this vCPU/CPU ratio.

Charles Killmer, VCP

If you found this or other information useful, please consider awarding points for "Correct" or "Helpful".