Dynamic Packet Fragmentation for Increased Virtual Channel Utilization in On-Chip Routers

Conventional packet-switched on-chip routers provide good resource sharing while minimizing latencies through various techniques. A Virtual Channel (VC) is allocated on a per-packet basis and held until the entire packet exits the VC buffer. This sometimes leads to inefficient use of VCs at high network loads. A blocked packet can affect adjacent routers, resulting in a congestion propagation effect. In such a scenario, VC buffers may be empty although they are regarded as fully occupied by a blocked packet. This paper proposes a dynamic packet fragmentation technique which releases empty VC buffers by fragmenting packets and allowing other packets to use the freed VC buffers.