Utilizing shared data in chip multiprocessors with the Nahalal architecture

Abstract

This paper addresses a new cache organization in a Chip Multiprocessors (CMP) environment. We introduce Nahalal, an architecture whose novel floorplan topology partitions cached data according to its usage (shared versus private data), and thus enables fast access to shared data for all processors while preserving the vicinity of private data to each processor. The Nahalal architecture combines the best of both shared caches and private caches, enabling fast accesses to data as in private caches while eliminating the need for inter-cache coherence transactions. Detailed simulations in Simics demonstrate that Nahalal decreases cache access latency by up to 41.1% compared to traditional CMP designs, yielding performance gains of up to 12.65% in run time.