kernel  /boot/xen-4.2.2.gz xsave=0 dom0_max_vcpus=1 dom0_vcpus_pin

xl vcpus-list 로 확인

 

domU를 pining하면 cpu usage를 각각 볼 수 있음

cpu usage는 mpstat으로

 

 

 

 

 

Can I dedicate a cpu core (or cores) only for dom0?

Yes, you can. It might a good idea especially for systems running IO intensive guests. Dedicating a CPU core only for dom0 makes sure dom0 always has free CPU time to process the IO requests for the domUs. Also when dom0 has a dedicated core there are less CPU context switches to do, giving better performance.

Specify "dom0_max_vcpus=X dom0_vcpus_pin" options for Xen hypervisor (xen.gz) in grub.conf and reboot.

After rebooting you can verify with "xl vcpu-list" that dom0 vcpus are pinned to only use the matching physical cpus.

The next step is to configure all the guests (domUs) to NOT use those same physical cpus. This can be done by specifying for example cpus="2-7" to all /etc/xen/<guest> cfgfiles. This example would leave physical cpus/cores 0 and 1 only for dom0, and make the guests use cpus/cores 2 to 7.