Efficient broadcast algorithms for heterogeneous networks of workstations

Heterogeneous networks of workstations (HNOW) have become an alternative platform for high performance computing because of the commodity nature of workstations and the advent of high speed networking. For the use of HNOW in high performance computing, efficient algorithms must be designed for collective communication operations. Algorithms designed for homogeneous systems (NOW) perform poorly when used in heterogeneous systems. In this paper, we propose two algorithms (all-to-all shortest path based (AASP) and alternate fast-slow (AFS)) to implement efficient broadcast operations on HNOW. We compare the performance of both the above algorithms with another algorithm, Earliest Completion Edge First (ECEF) with lookahead in the literature for collective communication on HNOW. We studied the performance of our algorithms with different parameters such as latency, bandwidth, number of nodes, message-size, single and multiple clusters by simulation. Experiments show that our algorithms outperform ECEF with lookahead by up to 40%.