libvirt

ntk148v · Sep 17, 2024 · 1c929ca · 1c929ca
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+# Virtual machine CPU metrics
+
+Libvirt virtual machine (domain) has multiple CPU metrics:
+
+- `VIR_DOMAIN_CPU_STATS_CPUTIME`: cpu usage (sum of both vcpu and hypervisor usage) in nanoseconds, as a ullong.
+- `VIR_DOMAIN_CPU_STATS_SYSTEMTIME`: cpu time charged to system instructions in nanoseconds, as a ullong.
+- `VIR_DOMAIN_CPU_STATS_USERTIME`: cpu time charged to user instructions in nanoseconds, as a ullong.
+- `VIR_DOMAIN_CPU_STATS_VCPUTIME`: vcpu usage in nanoseconds (cpu_time excluding hypervisor time), as a ullong.
+
+If you want to visualize the CPU usage of the machine, you should use `VIR_DOMAIN_CPU_STATS_VCPUTIME` instead of `VIR_DOMAIN_CPU_STATS_CPUTIME` because `VIR_DOMAIN_CPU_STATS_CPUTIME` can be over 100%, it doesn't look right.