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Virtual Box doesn't use all the Processor Power

Posted: 16. Nov 2008, 19:06
by Claymore
Hi, I'm having a small problem with Virtual Box under Windows XP 64 bits.

I have Windows XP Pro 32bits SP3 installed in a guest machine and I'm using VT extensions (i have an intel Q9450 processor), and in the other day i run a benchmark in the guest machine. I notice that the task manager of the XP SP3 guest machine indicated that it was using 100% of the processor availability but in the Main system (Windows XP 64 bits), the average of the four cores was bellow 20%.

My question is, is this a bug? Is Virtual Box incapable of using all of my Processor Power? If this is a Virtual Box configuration Problem, does anyone knows how to solve this problem?

Any help is welcome! :)

Posted: 17. Nov 2008, 16:38
by TerryE
Hi Claymore and welcome to our forum. You might want to take this opportunity to browse the Forum Posting Guide. This contains some useful tips on how to search for VBox knowledge and how to frame Qs.

This one is quite a common Q. The VBox VMM only emulates a single CPU VM, but unless you set the processor affinity, it will flip between cores at each context switch so each one looks as if it is 25% loaded. I suggest that the 20 vs. 25% is just rounding.

Posted: 17. Nov 2008, 16:56
by Claymore
Thanks for the welcome!

I understand the problem, and yeah, the 20 was a round up, it actually stays stable at 25%.
Since VB doesn't suport multicore, for the time beeing, there's nothing to do about it...

Thanks for the help anyway :)

Posted: 17. Nov 2008, 17:16
by TerryE
Claymore wrote:Since VB doesn't suport multicore, for the time beeing, there's nothing to do about it...
Split your workload over multiple VMs. TeHe.