Performance issues of message transmission on cluster-based multicomputer

With great interest in high performance, scalability, and availability, we have been developing cluster based multicomputer, scalable parallel architecture computer based on crossbar network (SPAX), and its operating system (MISIX). Because the MISIX is a microkernel based operating system, both local communication and remote communication between many servers are indispensable. A local communication mechanism is performed within a local memory, but a remote communication is completed through XNIF boards on SPAX. One of the most significant problems is how to transmit many messages to remote nodes rapidly. We investigate the performance issues involved in implementing remote communication primitives on a high speed network. Experimental results concerning the management of send buffers, the effect of confirmation interrupt, the selection of proper message type, and the management of reception buffers are presented and evaluated.