System Area Networks (SANs), which usually accept arbitrary topologies, have been used to connect nodes in PC/WS clusters or high-performance storage systems. Although deadlock-free routings, multicasts, and topologies for SANs have been widely developed, their evaluation on real PC clusters was rarely done. Thus, the evaluation of routings, multicasts and topologies in real systems is important to analyze their impact on the total systems and validate their simulation results. In this paper,

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... implement and evaluate deadlock-free routings and unicast-based multicasts under various topologies and channel buffer sizes on a PC cluster called RHiNET-2 with 64 hosts. Execution results show that descending layers (DL) routing and structured channel pools improve up to 57% of bandwidth and 34% of barrier synchronization time compared with up*/down* routing. They also show that, by visiting hosts in numerical order, execution time of unicast-based barrier synchronization is improved up to 28% compared with that in random order. However, channel buffer sizes don't affect the bandwidth in the RHiNET-2 cluster. In addition to fundamental evaluation, we appraise them using NAS Parallel Benchmarks, and the DL routing achieves 3.2% improvement on their execution time compared with up*/down* routing.