SR-IOV offers performance benefits and tradeoffs similar to those of DirectPath I/O. DirectPath I/O and SR-IOV have similar functionalty but you use them to accomplish different things.

SR-IOV is beneficial in workloads with very high packet rates or very low latency requirements. Like DirectPath I/O, SR-IOV is not compatible with certain core virtualization features, such as vMotion. SR-IOV does, however, allow for a single physical device to be shared amongst multiple guests.

With DirectPath I/O you can map only one physical funtion to one virtual machine. SR-IOV lets you share a single physical device, allowing multiple virtual machines to connect directly to the physical funtion.

This functionality allows you to virtualize low-latency (less than 50 microsec) and high PPS (greater than 50,000 such as network appliances or purpose built solutions) workloads on a VMWorkstation.