Management of multilevel queues for shared network adapters

Technology for managing queuing resources of a shared network adapter is disclosed. The technology includes selectively transferring data from data transmission sources to a queue of the shared network adapter based on status indications from the shared network adapter regarding availability of queuing resources at the shared network adapter. In addition, the technology also includes features for selectively controlling transfer rates of data to the shared network adapter from applications, virtual network stations, other virtual adapters, or other data transmission sources. As one example, this selective control is based on how efficiently data from these data transmission sources are transmitted from the shared network adapter.