Included in the VMware vSphere 4.1 management station, the vStorage API for Array Integration (VAAI) can be used to off-load certain functions from the target VMware host to the storage array. With the tasks being performed more efficiently by the array instead of the target VMware host, performance can be greatly enhanced.
The HP P2000 Software Plug-in for VMware VAAI (VAAI Plug-in) allows offloading the following functions (primitives) to the MSA array:
o Full copy—enables the array to make full copies of data within the array, without the ESX server having to read and write the data.
o Block zeroing—enables the array to zero out a large number of blocks to speed up provisioning of virtual machines.
o Hardware assisted locking—provides an alternative means to protect the metadata for VMFS cluster-file systems, thereby improving the scalability of large ESX server farms sharing a datastore.