Hi Mikyung,
What does the NUMA topology look like inside your VMs, i.e., are you pinning memory nodes as well as CPUs? Do you have cpu numa xml elements in your libvirt domain xml, e.g., like:
...
<cpu>
...
<numa>
<cell id='0' cpus='0-3' memory='512000' unit='KiB'/>
<cell id='1' cpus='4-7' memory='512000' unit='KiB' memAccess='shared'/>
</numa>
...
</cpu>
...
?
