You can allocate memory resources for a virtual machine and specify reservations, limits, and shares.

A virtual machine has three user-defined settings that affect its memory resource allocation.

Limit

Places a limit on the consumption of memory for a virtual machine. This value is expressed in megabytes.

Reservation

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

Shares

Each virtual machine is granted a number of memory shares. The more shares a virtual machine has, the more often it gets a time slice of a memory when there is no memory idle time. Shares represent a relative metric for allocating memory capacity. For more information about share values, see the Resource Management Guide.

Assigning a virtual machine a reservation larger than its configured memory is wasteful. The vSphere Client does not allow you to make such an assignment on the Resources tab. If you give a virtual machine a large reservation and then reduce its configured memory size on the Hardware tab, the reservation is reduced to match the new configured memory size. You must power off the virtual machine before configuring memory resources.

1

In the vSphere Client inventory, right-click the virtual machine and select Edit Settings.

2

Click the Resources tab and select Memory.

3

Allocated the memory capacity for this virtual machine.

Option

Description

Shares

The values Low, Normal, High, and Custom are compared to the sum of all shares of all virtual machines on the server and, on ESX/ESXi hosts, the service console. You can use share allocation symbolic values to configure their conversion into numeric values.

Reservation

Guaranteed memory allocation for this virtual machine.

Limit

Upper limit for this virtual machine’s memory allocation.

Unlimited

No upper limit is specified.

4

Click OK to save your changes and close the dialog box.