No abstract

A load sharing problem involving the optimal load allocation of divisible loads in a distributed computing system consisting of N processors intercoiinected through a bus-oriented network is investigated. For a diifisible load, the workload is infinitely divisible so that each fraction of the workload can be distributed and independently computed on each processor. For the first time in divisible load theory, an analysis is provided in the case when the processor speed andl the channel speed are time varying due to background jobs submitted to the distributed system with nonnegligible communication delays. A numerical method to calculate the average of the time-varying processor speed and the channel speed and sin algorithm to find the optimal allocation of the workload to minimize the total processing finish time are proposed via a deterministic analysis. A stochastic analysis which makes use of Markoviain queueing theory is introduced for the case when arrival and departure times of the background jobs are not known.

Abstract-A bus oriented network where there is a charge for the amount of divisible load processed on each processor is investigated. A cost optimal processor sequencing result is found which involves assigning load to processors in nondecreasing order of the cost per load characteristic of each processor. More generally, one can trade cost against solution time. Algorithms are presented to minimize computing cost with an upper bound on solution time and to minimize solution time with an upper bound on cost. As an example of the use of this type of analysis, the effect of replacing one fast but expensive processor with a number of cheap but slow processors is also discussed. The type of questions investigated here are important for future computer utilities that perform distributed computation for some charge.