Virtual machine hardware Version 7 introduced a new VMware Paravirtual storage adapter (PVSCSI). It is considered a high-performance storage adapter recommended for VMs with high I/O usage. PVSCSI can handle high I/O with higher storage throughput while keeping CPU utilization low.
In ESXi 4, the LSI Logic adapter performs better than PVSCSI for VMs doing less than 2,000 IOPS.
More details are available in the VMware KB 1017652 article at http://kb.vmware.com/kb/1017652.
The following operating systems support PVSCSI:
These operating systems don't include drivers ...