1. A computer readable medium comprising software instructions for reclaiming transmit descriptors, wherein the software instructions, when executed, perform a method, the method comprising: configuring a media access control (MAC) to execute a first MAC layer thread to reclaim a first plurality of transmit descriptors (TDs) from a first hardware transmit ring (HTR) using a first reclaim algorithm, wherein the first HTR comprises a transmit descriptor ring (TDR) and resides on a physical network interface card (NIC), wherein the first MAC layer thread is executing on a host operatively connected to the physical NIC, and wherein the first reclaim algorithm is associated with a first transmission pattern and a first TDR status; receiving, by a virtual NIC (VNIC) executing within the MAC layer, a first plurality of packets; forwarding the first plurality of packets to a device driver on the host associated with the physical NIC; and forwarding the first plurality of packets from the device driver to the physical NIC using the first plurality of TDs, wherein the first plurality of TDs are reclaimed by the first MAC layer thread according to the first reclaim algorithm.