Enabling software management for multicore caches with a lightweight hardware support

Abstract

The management of shared caches in multicore processors is a critical and challenging task. Many hardware and OS-based methods have been proposed. However, they may be hardly adopted in practice due to their non-trivial overheads, high complexities, and/or limited abilities to handle increasingly complicated scenarios of cache contention caused by many-cores. In order to turn cache partitioning methods into reality in the management of multicore processors, we propose to provide an affordable and lightweight hardware support to coordinate with OS-based cache management policies. The proposed methods are scalable to many-cores, and perform comparably with other proposed hardware solutions, but have much lower overheads, therefore can be easily adopted in commodity processors. Having conducted extensive experiments with 37 multi-programming workloads, we show the effectiveness and scalability of the proposed methods. For example on 8-core systems, one of our proposed policies improves performance over LRU-based hardware cache management by 14.5% on average.