This value reports how many successfully received Ethernet messages are currently waiting to be moved by the DMA engine into global memory buffers. An administrator treats a persistently high value as a sign that the move from local reception to global memory is lagging, which can eventually force the receiver to drop frames once its own buffers fill. For example, if this queue length keeps growing during a sustained traffic load, it suggests the global memory DMA transfer, not the Ethernet link itself, is the throughput constraint.