On 27/02/14 15:06, Bei Guan wrote:
Hi,

I run a PV DomU with 1 vcpu on Xen. I pin the vcpu to a physical CPU core, such as core 3. Then, I run a cpu-bound process in DomU and the vcpu utilization is 100% (got it with "xentop" in Dom0).
However, when I use "top" in Dom0 to see the physical CPU utilization, the CPU core 3 utilization is zero or less than 1%. The utilization expected of CPU core 3 is also 100% like the vcpu. Is it? Why I cannot get the accurate physical CPU utilization with "top" command in Dom0?

Any advice is appreciated. Thank you for your time.

Xen is not KVM; dom0 is just another VM as far as Xen is concerned, so dom0's cpu3 is not domU's cpu3.

Top in dom0 shows dom0's virtual cpu utilisation.  I am not aware of a utility like top which gives the physical cpu information, distributed by physical cpu.

~Andrew