Many applications in parallel processing have to traverse large, implicitly de ned trees with irregular shape. The receiver initiated load balancing algorithm asynchronous random polling has long been known to be very e cient for these problems in practice. Tight bounds for the parallel execution time in the LogP model are derived based on the parameters of a problem model called tree shaped computations. This model incorporates the problem size, the cost for basic operations, a measure of granularity and an easy to quantify parameter which limits irregularity. Then, with poll-and-shu e, an asymptotically even more e cient algorithm is introduced. By using predominantly local communications it increases the usable communication bandwidth on hypercubic networks and meshes by a logarithmic factor. These analytic results are complemented by practical re nements and implementation results which successfully apply a portable and reusable library on machines with up to 1024 processors. Keywords: adaptive granularity control, asynchronous algorithm, hypercubic and mesh network, parallel backtrack search, parallel random permutation, randomized load balancing algorithm 1
Using the logp model, Sanders REF analyzes a receiver-initiated load-balancing algorithm for a subclass of tree-shaped computations, presenting bounds that show the approach to be theoretically efficient.
Randomized Receiver Initiated Load Balancing Algorithms for Tree Shaped Computations
The Computer Journal
Computer Science