[libvirt-users] Any recommendation about benchmarking tools on Linux virtual machine?

Hi all, Do you have any recommendation about benchmarking tools on Linux virtual machine for measure the potential performance hit by virtualization, especially on multi-threads computation, since I doubt if the CentOS VM can fully make use of the 32 vCPUs (out of 64 physical cores) that I allocated to it. Regards, Allen 2014-11-05 Allen Qiu