Memory-Based Communication Facilities and Asymmetric Distributed Shared Memory

In general-purpose parallel and distributed systems, performance of the protected and virtualized user-level communications and synchronizations is the most crucial issue to realize efficient execution environments. We proposed a novel high-speed user-level communication and synchronization scheme “Memory-Based Communication Facilities (MBCF)” for a general-purpose system with an off-the-shelf communication-hardware. The MBCF realizes the direct remote-memory-accesses in user-task-space and offers programmers and compilers a large shared-memory space. This paper describes outlines and characteristics of the MBCF, and evaluates basic performance of the MBCF/Ether which is the first sample implementation with 100BASE-TX interfaces. The evaluation tells that its peak bandwidth at half-duplex mode is 11.2Mbyte/sec and its round-trip latency is 49 sec. Finally, we introduce a brand-new remote cache scheme “Asymmetric Distributed Shared Memory (ADSM)”, which is suitable for the MBCF and optimizing compilers, and show the effects of optimization methods for the ADSM.