Optimized memory-based messaging: Leveraging the memory system for high-performance communication

Memory-based messaging, passing messages between programs through a shared memory segment, is a recognized technique for efficient communication that takes direct advantage of memory system performance. However, the conventional operating system and hardware support for this approach is inefficient, especially in large-scale multiprocessor systems. This paper describes interface, software and hardware optimizations for memory-based messaging that efficiently exploit the basic mechanisms of the memory system to provide superior communication performance. We describe the overall model of optimized memory-based messaging, its implementation in an operating system kernel and hardware support for this approach in a scalable multiprocessor architecture. The optimizations include address-valued signals, message-oriented memory consistency and automatic signaling on write. Performance evaluations show these extensions provide a three-to-five-fold improvement in communication performance over a comparable software-only implementation.