Theory and operation of the Warwick multiprocessor scheduling (MS) system

Abstract

This paper is concerned with the application of performance prediction techniques to the optimisation of parallel systems, and, in particular, the use of these techniques on-the-fly for optimising performance at run-time. In contrast to other performance tools, performance prediction results are made available very rapidly, which allows their use in real-time environments. When applied to program optimisation, this allows consideration of run-time variables such as input data and resource availability that are not, in general, available during the traditional (ahead-of-time) performance tuning stage. The main contribution of this work is the application of predictive performance data to the scheduling of a number of parallel tasks across a large heterogeneous distributed computing system. This is achieved through use of just-in-time performance prediction coupled with iterative heuristic algorithms for optimisation of the meta-schedule. The paper describes the main theoretical considerations for development of such a scheduling system, and then describes a prototype implementation, the MS scheduling system, together with some results obtained from this system when operated over a medium-sized (campus-wide) distributed computing network