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CPU Counters

Performance counters are modeled using the PerfCounterInfo data object type. Each instance of a PerfCounterInfo data object contains metadata about a specific metric available from the system. The cpu group of performance counters supports metrics for CPU utilization per host, per virtual machine, per resource pool, or per compute resource, as appropriate.

Legend:V=VirtualMachine|H=HostSystem|R=ResourcePool|C=ComputeResource|D=OtherDevice
Counter StatsType Unit Level RollupType Label      Entity
VHRC
cpuentitlement absolute number 1 latest Worst Case Allocation ο ο
Amount of CPU resources allocated to the virtual machine or resource pool based on the total cluster capacity and the resource configuration (reservations, shares, and limits) on the resource hierarchy. cpuentitlement is computed based on an ideal scenario in which all virtual machines are completely busy and the load is perfectly balanced across all hosts.

This counter is for internal use only and is not useful for performance monitoring.
guaranteed delta millisecond 3 latest CPU Guaranteed ο ο ο
Not supported for ESX 4.x systems, except through vCenter Server. CPU time that is reserved for the entity. For virtual machines, this measures CPU time that is reserved, per virtual CPU (VCPU).

This counter has been deprecated and should not be used to monitor performance.
idle delta millisecond 2 summation CPU Idle ο ο ο
Total time that the CPU spent in an idle state (meaning that a virtual machine is not runnable).
ready delta millisecond 1 summation CPU Ready ο ο ο
Percentage of time that the virtual machine was ready, but could not get scheduled to run on the physical CPU. CPU ready time is dependent on the number of virtual machines on the host and their CPU loads.
reservedCapacity absolute megaHertz 2 average CPU Reserved Capacity ο ο
Total CPU capacity reserved by the virtual machines.
system delta millisecond 3 summation CPU System ο ο ο
Amount of time spent on system processes on each virtual CPU in the virtual machine. This is the host view of the CPU usage, not the guest operating system view.
totalmhz rate megaHertz 1 average CPU total ο ο ο
Total amount of CPU resources of all hosts in the cluster. The maximum value is equal to the frequency of the processors multiplied by the number of cores.

totalmhz = CPU frequency x number of cores

For example, a cluster has two hosts, each of which has four CPUs that are 3GHz each, and one virtual machine that has two virtual CPUs.

VM totalmhz = 2 vCPUs x 3000MHz = 6000MHz
Host totalmhz = 4 CPUs x 3000MHz = 12000MHz
Cluster totalmhz = 2 x 4 x 3000MHz = 24000MHz
usage rate percent 1 (4) average
(minimum)
(maximum)
(none)
CPU Usage (Average)
CPU Usage (Minimum)
CPU Usage (Maximum)
CPU Usage (None)
CPU usage as a percentage during the interval.
  • VM - Amount of actively used virtual CPU, as a percentage of total available CPU. This is the host's view of the CPU usage, not the guest operating system view. It is the average CPU utilization over all available virtual CPUs in the virtual machine. For example, if a virtual machine with one virtual CPU is running on a host that has four physical CPUs and the CPU usage is 100%, the virtual machine is using one physical CPU completely.

    virtual CPU usage = usagemhz / (# of virtual CPUs x core frequency)

  • Host - Actively used CPU of the host, as a percentage of the total available CPU. Active CPU is approximately equal to the ratio of the used CPU to the available CPU.

    available CPU = # of physical CPUs x clock rate

    100% represents all CPUs on the host. For example, if a four-CPU host is running a virtual machine with two CPUs, and the usage is 50%, the host is using two CPUs completely.

  • Cluster - Sum of actively used CPU of all virtual machines in the cluster, as a percentage of the total available CPU.

    CPU Usage = CPU usagemhz / effectivecpu

usagemhz rate megaHertz 1 (4) average
(minimum)
(maximum)
(none)
CPU Usage in MHz (Average)
CPU Usage in MHz (Minimum)
CPU Usage in MHz (Maximum)
CPU Usage in MHz (None)
CPU usage, as measured in megahertz, during the interval.
  • VM - Amount of actively used virtual CPU. This is the host's view of the CPU usage, not the guest operating system view.
  • Host - Sum of the actively used CPU of all powered on virtual machines on a host. The maximum possible value is the frequency of the processors multiplied by the number of processors. For example, if you have a host with four 2GHz CPUs running a virtual machine that is using 4000MHz, the host is using two CPUs completely.

    4000 / (4 x 2000) = 0.50

used delta millisecond 3 summation CPU Used ο ο ο
Total CPU usage.
wait delta millisecond 3 summation CPU Wait ο ο ο
Total CPU time spent in wait state.

 

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