You can change the amount of CPU resources allocated to a virtual machine by using the shares, reservations, and limits settings.

Before you begin

Required Privilege: Virtual machine > Configuration > Change resource

About this task

A virtual machine has the following user-defined settings that affect its CPU resource allocation.

Limit

Places a limit on the consumption of CPU time for a virtual machine. This value is expressed in MHz.

Reservation

Specifies the guaranteed minimum allocation for a virtual machine. The reservation is expressed in MHz.

Shares

Each virtual machine is granted a number of CPU shares. The more shares a virtual machine has, the more often it gets a time slice of a CPU when there is no CPU idle time. Shares represent a relative metric for allocating CPU capacity.

Note:

Virtual machine hardware versions 9, 10 and 11 features are read-only when connected to the ESXi host or vCenter Server system using the vSphere Client.

Procedure

  1. In the vSphere Client inventory, right-click the virtual machine and select Edit Settings.
  2. Click the Resources tab and select CPU.
  3. Allocate the CPU capacity for this virtual machine.

    Option

    Description

    Shares

    CPU shares for this virtual machine in relation to the parent’s total. Sibling virtual machines share resources according to their relative share values bounded by the reservation and limit. Select Low, Normal, or High, which specify share values respectively in a 1:2:4 ratio. Select Custom to give each virtual machine a specific number of shares, which express a proportional weight.

    Reservation

    Guaranteed CPU allocation for this virtual machine.

    Limit

    Upper limit for this virtual machine’s CPU allocation. Select Unlimited to specify no upper limit.

  4. Click OK to save your changes.