Increasing the amount of CPU assigned to a virtual machine

Products

• VMware vCenter Server
• VMware vSphere ESXi

Issue/Introduction

This article describes how to increase the assigned CPU cycles of a virtual machine. Increasing the amount of CPU cycles assigned to a virtual machine may be required if its CPU requirements have changed since the time of the virtual machine creation. The article also addresses slow operating system performance caused by insufficient CPU cycles.

Symptoms:

Resolution

You can only increase the assigned CPU cycles on an ESX Server virtual machine. If this is a virtual machine running under any other product, there is no direct way of increasing its assigned CPU cycles. If your host has multiple CPUs or CPU cores, it is possible to set processor affinity among virtual machines so that one or more CPUs are not used by any other virtual machine. For more information, see Using CPU Affinity to Assign Virtual Machines Specific Processors in the Resource Management Guide. Alternatively, the host hardware must be upgraded or the virtual machine moved to a different host.

To increase the assigned CPU cycles on an ESX Server virtual machine:

Note: Lab Manager does not currently support changing a virtual machine's CPU assignment.

1. Ensure that the virtual machine is powered off.
2. With the Virtual Infrastructure Client connect to the ESX Server host that is managing the virtual machine or to VirtualCenter.
3. Right-click the entry for the virtual machine.
4. Click Properties.
5. Click the Resources tab.
6. Set the CPU limit as required.

Additional Information

仮想マシンに割り当てられる CPU 使用量を増加する
增加分配给虚拟机的 CPU 量