High CPU Load @ Virtualbox and Testagents

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1

Hy,

i have a Server equipped with 8 Xeon(R) E5620 @ 2.40GHz and 20 Gbyte Memory.
It should be enough to run 4 Win7 32Bit Clients in a virtual environment.
nevertheless i have a strong cpu utilisation in some peaks, which causes long loading time of different elements (s. attached image).
The CPU Peaks occuring with IE9, Chrome and Firefox
The utilisation peaks are variable, but they always bother the measurement and therewith my speedindex result.
the following measures achieve no success :

  • Switching down VM to only one running OS
  • adding more CPU Power and Memory to the instances
  • increase swapfile size on Win7
  • increase the priority to the Browsersession

Measuring the same sides with a dedicated single agent keeps the CPU load at a base Level and provides appropriate results.

Does anybody has an idea where my configuration mistake is located ?

thanks and regards
Heiko

2

Try telling Windows to use a different real-time clock - windows 7 - Setting "USEPMTIMER" with BCDEDIT - Super User Sometimes that helps.

Have you installed the gues additions drivers? Chapter 4. Guest Additions

I don’t have experience testing it on virtual box. I do know that KVM has some issues, Xen is a bit better than KVM but best of all of them is VMWare (with ESXi being the best all-around).

3

Hi Pat,

i switched to the VMware vSphere Hypervisor (ESXi). Comparing to a single system, the CPU Load is still higher, but VMware doesn´t clip like virtual box.
I have installed 4x Win7 Clients , each 4 Gbyte Ram , 2 Cores of the CPU on a VMServer Xeon E5620 with 18 Gbyte of RAM.
So, up to now there is no negative impact of higher load time due to exceeding CPU load.
Thanks for the proposal !