ServerNet-II: a Reliable Interconnect for Scalable High Performance Cluster Computing
Alan Heirich, David García, Michael Knowles · 1998
The ServerNet-II System Area Network (SAN) is Compaq's native hardware implementation of the Virtual Interface (VI) Architecture. The ServerNet-II SAN implements the VI message passing and remote memory operation models. These models are supported by a VI Processor (VIP) mechanism for inter-process communication and by a Data Channel Engine (DCE) mechanism for intelligent scalable I/O across a network. Communication protocols are implemented in native hardware to eliminate the CPU overhead that is normally associated with message passing. Data links provide 1.25 + 1.25 gigabits per second of bi-directional bandwidth at distances up to 5 kilometers over standard gigabit Ethernet physical media. A Fat Pipe capability increases the e ective bandwidth to 5.0 + 5.0 gigabits per second by merging sets of parallel links. This capability makes it possible to construct network topologies in which the bandwidth distribution is non-uniform. Best-case latency for short messages has been measured in single-digit microseconds. The ServerNet-II SAN is a reliable technology with fault-tolerant mechanisms at multiple architectural levels. These mechanisms automatically recover from link level failures while maintaining guarantees of reliable and ordered message delivery. This paper presents an introduction to the ServerNet-II SAN with a focus on it's use in scienti c and technical cluster computing.