ESXi can determine whether a virtual machine needs hardware support for virtualization. ESXi makes this determination based on the processor type and the virtual machine. Overriding the automatic selection can provide better performance for some use cases.

You can use software MMU when your virtual machine runs heavy workloads, such as Translation Lookaside Buffers (TLBs) intensive workloads that have significant impact on the overall system performance. However, software MMU has a higher overhead memory requirement than hardware MMU. So, to support software MMU, the maximum overhead supported for virtual machine limit in the VMkernel needs to be increased. You can configure your virtual machine with up to 128 CPUs if your virtual machine host has ESXi 6.0 and later compatibility (hardware version 11).


To take advantage of all features that virtual hardware version 13 provides, use the default hardware MMU setting.


  1. Right-click a virtual machine in the inventory and select Edit Settings.
  2. On the Virtual Hardware tab, expand CPU, and select an instruction set from the CPU/MMU Virtualization drop-down menu.
  3. Click OK.