Hi All, currently we encountered two issues with the CPU frequency of the QEMU-KVM guest.
We pin the VCPUs of a guest to a few of the host cores and set the "cpupower governor" of these cores to "performance" mode to use the max CPU frequency. However, - the guest displays constant CPU freuquency in /proc/cpuinfo, no matter how much of the workload is - even the VCPUs are 100% loaded, the cores on which they are pinned show only 94% of their max CPU frequency >From the AMD SDM we leanred that CPU frequency is calculated from the values of two registers - MPERF and APERF, and is read to /proc/cpuinfo by queying a CPUID. The first issue was also seen in [1,2]. We'd like to know: - is there a way to display the host CPU frequency correctly by the VCPUs in the guest ? - does the power mode setting (e.g. ondemand - > performance) in a guest change the power mode of the pinned host cores ? Thank you very much for your reply. [1] https://bugzilla.redhat.com/show_bug.cgi?id=670104 [2] https://lists.nongnu.org/archive/html/qemu-devel/2013-08/msg01875.html Yu Zhang @IONOS Compute Platform
