Modeling of a high speed network to maximize throughputperformance : the experience of BIP over MyrinetLoic

High speed networks are now providing incredible performances. Software evolution is slow and the old protocol stacks are no longer adequate for these kind of communication speed. When throughput increases, the latency should decrease as much in order to keep the system balance. With the current network technology, the main bottleneck is most of the time the software that makes the interface between the hardware and the user. We designed and implemented new protocols of transmission targeted rst to parallel computing that squeeze the most out of the high speed Myrinet network, giving all the speed to the applications. A precise modeling of the high speed hardware was necessary to analytically determine the optimal pipelines parameters. This modeling and design is presented here as well as experimental results that lead to achieve real Gigabit/s throughput and less than 5s latency with half of the best performance (n 1=2) for 4KBytes messages on a cluster of PC workstations with this network hardware. Moreover, our networking results compare favorably with the expensive parallel computers or ATM LANs.