Abstract :
Summary form only given. The 2008 DARPA Exascale study was one of the first in-depth attempts to project ahead key characteristics for high-end massively parallel systems on the basis of technology trends, architectures, and computational kernels, and identified four major challenges for future systems designs. It focused on a single benchmark, Linpack, and identified two distinct classes of architectures: “heavyweight” and “lightweight.” This talk is a continuation of a series of updates to that study, and includes not only the most recent technology projections but also several new benchmarks for which significant multi-year data exists, and new classes of architectures that have emerged since then. The talk will address changes in characteristics (both before and after the seminal year of 2004 where multi-core took over), and how those characteristics are likely to project into the future. A series of vignettes on specific features will provide insight into areas where current design trends are becoming over or under-balanced. Special attention is given to both computational energy and memory.