The hardware offloading and acceleration benefits of VAAI in vSphere are well documented. Check here for one of many explanations.  I am frequently asked by customers how to know if VAAI is enabled and where to check.

Here are the instructions to validate that the VAAI block primitives are enabled in vSphere.

Verify Hardware Assisted (Accelerated) Locking is enabled

  1. From the vSphere Client click Home > Inventory > Hosts and Clusters
  2. Select a host, click the Configuration tab, and select Advanced Settings
  3. Select VMFS3 and note that the VMFS3.HardwareAcceleratedLocking parameter is set to 1

Verify Block Zeroing (Hardware Accelerated Zero) is enabled

  1. From the vSphere Client click Home > Inventory > Hosts and Clusters
  2. Select a host, click the Configuration tab, and select Advanced Settings
  3. Select DataMover and note that the DataMover.HardwareAcceleratedInit parameter is set to 1

Verify Hardware Accelerated Copy is enabled

  1. From the vSphere Client click Home > Inventory > Hosts and Clusters
  2. Select a host, click the Configuration tab, and select Advanced Settings
  3. Select DataMover and note that the DataMover.HardwareAcceleratedMove parameter is set to 1