Configuring Virtual CPUs and Memory
To configure the capabilities of a virtual machine, you use properties of the VirtualMachineConfigSpec data object to specify the machine characteristics available to the guest operating system. The guest uses these capabilities in the same way as resources on a physical machine.
Configuring Virtual CPUs
Set the number of virtual CPU cores for the
virtual machine with the VirtualMachineConfigSpec.numCPUs
property. Legal
values for this property change depending on the guestosid value you specify. If you use
VirtualMachineConfigSpec
to update the virtual machine properties, you
can omit this property to leave it unchanged.
The guest operating system acts as if it had
numCPUs
cores available at all times, but the host's physical resources
are shared by all its virtual machines. The host allocates physical cores in time slices aa
backing for virtual cores. For information about how to specify guidance for resource
allocation, see Configuring Resource Allocation Constraints for Virtual Machines.
Configuring Multi-Core CPUs
Set the number of cores per CPU chip with the
VirtualMachineConfigSpec.numCoresPerSocket
property. The value must be an
integral divisor of VirtualMachineConfigSpec.numCPUs
. The default value is
1
if the property is omitted for virtual machine creation. If you use
VirtualMachineConfigSpec
to update the virtual machine properties, you
can omit this property to leave it unchanged.
Configuring Memory
Set the RAM size for a virtual machine with the
VirtualMachineConfigSpec.memoryMB
property. If you use
VirtualMachineConfigSpec
to update the virtual machine properties, you
can omit this property to leave it unchanged.
The guest operating system acts as if it had
memoryMB
available at all times, but the host's physical resources are
shared by all its virtual machines. The amount of physical memory available as backing for
virtual machines can vary over time, and it can affect virtual machine performance. For
information about how to specify guidance for resource allocation, see Configuring Resource Allocation Constraints for Virtual Machines.