BIB-VERSION:: CS-TR-v2.0
          ID:: STAN//CS-TR-94-1506
       ENTRY:: February 28, 1994
ORGANIZATION:: Stanford University, Department of Computer Science
       TITLE:: Optimized Memory-Based Messaging: Leveraging the Memory
               System for High-Performance Communication
        TYPE:: Technical Report
      AUTHOR:: Cheriton, David R.
      AUTHOR:: Kutter, Robert A.
        DATE:: February 1994
       PAGES:: 25
    ABSTRACT:: Memory-based messaging, passing messages between programs
               using shared memory, is a recognized technique for efficient
               communication that takes advantage of memory system
               performance. However, the conventional operating system
               support for this approach is inefficient, especially for
               large-scale multiprocessor interconnects, and is too complex
               to effectively support in hardware. This paper describes
               hardware and software optimizations for memory-based
               messaging that efficiently exploit the 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.
       NOTES:: [Adminitrivia V1/Prg/19940228]
         END:: STAN//CS-TR-94-1506