More on Scheduling Block-Cyclic Array Redistribution

Frédéric Desprez (1) , Stéphane Domas , Jack J. Dongarra , Antoine Petitet , Cyril Randriamaro , Yves Robert

1 REMAP - Regularity and massive parallel computing

This article is devoted to the run-time redistribution of one-dimensional arrays that are distributed in a block-cyclic fashion over a processor grid. In a previous paper, we have reported how to derive optimal schedules made up of successive communication-steps. In this paper we assume that successive steps may overlap. We show how to obtain an optimal scheduling for the most general case, namely, moving from a CYCLIC(r) distribution on a P-processor grid to a CYCLIC(s) distribution on a Q-processor grid, for arbitrary values of the redistribution parameters P, Q, r, and s. We use graph-theoretic algorithms, and modular algebra techniques to derive these optimal schedulings.

Mots clés: DISTRIBUTED ARRAYS; REDISTRIBUTION; HPF; ASYNCHRONOUS COMMUNICATIONS; SCHEDULING; BLOCK-CYCLIC DISTRIBUTION

Domaines: Autre [cs.OH]

Frédéric Desprez, Stéphane Domas, Jack J. Dongarra, Antoine Petitet, Cyril Randriamaro, et al.. More on Scheduling Block-Cyclic Array Redistribution. [Research Report] RR-3524, LIP RR-1998-17, INRIA, LIP. 1998. ⟨inria-00073160⟩