Scalable multi-cores with improved per-core performance using off-the-critical path reconfigurable hardware

Abstract

Scaling the number of cores in a multi-core processor constraints the resources available in each core, resulting in reduced per-core performance. Alternatively, the number of cores have to be reduced in order to improve per-core performance. In this paper, we propose a technique to improve the per-core performance in a many-core processor without reducing the number of cores. In particular, we integrate a Reconfigurable Hardware Unit (RHU) in each core. The RHU executes the frequently encountered instructions to increase the core's overall execution bandwidth, thus improving its performance. We also propose a novel integrated hardware/software methodology for efficient RHU reconfiguration. The RHU has low area overhead, and hence has minimal impact on the scalability of the multi-core. Our experiments show that the proposed architecture improves the per-core performance by an average of about 12% across a wide range of applications, while incurring a per-core area overhead of only about 5%. © 2008 Springer Berlin Heidelberg.