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.

Important: Modern x86 processors can fully support virtualized workloads without software assistance. So, the CPU/MMU Virtualization setting has been deprecated in ESXi 6.7 and later. The CPU/MMU Virtualization setting is available only for virtual machines with ESXi 6.5 and earlier compatibility.

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 must be increased.

Procedure

  1. Right-click a virtual machine in the inventory and select Edit Settings.
  2. On the Virtual Hardware tab, expand CPU, and select the Enabled check box to activate the I/O MMU options for a virtual machine.
    Note: To take advantage of all features that virtual hardware version 13 provides, use the default hardware MMU setting.
  3. Click OK.