8.11. Using PMU to Monitor Guest Virtual Machine Performance

In Red Hat Enterprise Linux 6.4, vPMU (virtual PMU) was introduced as a Technology Preview. vPMU is based on Intel's PMU (Performance Monitoring Units) and may only be used on Intel machines. PMU allows the tracking of statistics which indicate how a guest virtual machine is functioning.

Using performance monitoring, allows developers to use the CPU's PMU counter while using the performance tool for profiling. The virtual performance monitoring unit feature allows virtual machine users to identify sources of possible performance problems in their guest virtual machines, thereby improving the ability to profile a KVM guest virtual machine.

To enable the feature, the -cpu host flag must be set.

This feature is only supported with guest virtual machines running Red Hat Enterprise Linux 6 and is disabled by default. This feature only works using the Linux perf tool. Make sure the perf package is installed using the command:

# yum install perf.

See the man page on perf for more information on the perf commands.