Server Interconnection Network Project Description

Network performance in tightly-coupled multiprocessors typically degrades rapidly beyond network saturation.  Consequently, designers must keep a network below its saturation point by reducing the load on the network.   This becomes even more important with advent of multiple hardware contexts on a chip (e.g., single-chip multiprocessors or simultaneous multithreading) that can dramatically increase network load.  Congestion control via source throttling---a common technique to reduce the network load---prevents new packets from entering the network in the presence of congestion.  Unfortunately, prior schemes to implement source throttling either lack vital global information about the network to take the correct decision (whether to throttle or not) or depend on specific network parameters, network topology, or communication patterns.  The goal of this research is to develop self-tuned, global-knowledge based congestion control techniques for multiprocessor networks.