On Future Global Grid Communication Performance

For a grid network performance data set, we estimate propagation distances to get a lower bound on propagation delays. With a model for primary performance factors and assumptions about expected performance trends, we extrapolate to estimate the communication performance of a global grid in ten years time. Communication pipes are getting fatter, but due to simple propagation delays, are not getting commensurately shorter. Hence, bandwidth-delay products will rise correlated to distance. Based on conservative estimates, the bandwidth-delay products will rise by a median factor of 5.2x with an increasing distribution to a strong mode at 7.1x. This clearly indicates that latency tolerance must be integral to applications at an increasingly smaller scale using established techniques such as caching, compression and pre-fetching coupled with coarse-grain, data-driven execution models to hide latency with throughput. With the extrapolated performance data, we use a simple pipeline model to estimate an “operating region” for work granularity and number of computational threads to hide latency with throughput. We then discuss implications for programming and execution models.