Performance Optimization of Cache Subsystem in General Purpose Graphics Processing Units: A Survey

With the development of process technology and the improvement of architecture, the parallel computing performance of GPGPU(general purpose graphics processing units) is updated a lot, which makes GPGPU applied more and more widely in the fields of high performance and high throughput. GPGPU can obtain high parallel computing performance, as it can hide the long latency incurred by the memory accesses via supporting thousands of concurrent threads. Due to the existance of irregular computation and memory access in some applications, the performance of the memory subsystem is affected a lot, especially the contention of the on-chip cache can become serious, and the performance of GPGPU can not be up to the maximum. Alleviating the contention and optimizing the performance of the on-chip cache have become one of the main solutions to the optimization of GPGPU. At present, the studies of the performance optimization of the on-chip cache focus on five aspects, including TLP(thread level parallelism) throttling, memory access reordering, data flux enhancement, LLC(last level cache) optimization, and new architecture design based on NVM(non-volatile memory). This paper mainly discusses the performance optimization research methods of the on-chip cache from these aspects. In the end, some interesting research fields of the on-chip cache optimization in future are discussed. The contents of this paper have important significance on the research of the cache subsystem in GPGPU.