Three-dimensional memory vectorization for high bandwidth media memory systems
Document typeConference report
PublisherInstitute of Electrical and Electronics Engineers (IEEE)
Rights accessOpen Access
Vector processors have good performance, cost and adaptability when targeting multimedia applications. However, for a significant number of media programs, conventional memory configurations fail to deliver enough memory references per cycle to feed the SIMD functional units. This paper addresses the problem of the memory bandwidth. We propose a novel mechanism suitable for 2-dimensional vector architectures and targeted at providing high effective bandwidth for SIMD memory instructions. The basis of this mechanism is the extension of the scope of vectorization at the memory level, so that 3-dimensional memory patterns can be fetched into a second-level register file. By fetching long blocks of data and by reusing 2-dimensional memory streams at this second-level register file, we obtain a significant increase in the effective memory bandwidth. As side benefits, the new 3-dimensional load instructions provide a high robustness to memory latency and a significant reduction of the cache activity, thus reducing power and energy requirements. At the investment of a 50% more area than a regular SIMD register file, we have measured and average speed-up of 13% and the potential for power savings in the L2 cache of a 30%.
CitationCorbal, J., Espasa, R., Valero, M. Three-dimensional memory vectorization for high bandwidth media memory systems. A: Annual IEEE/ACM International Symposium on Microarchitecture. "35th Annual IEEE/ACM International Symposium on Microarchitecture (MICRO-35): 18-22 November 2002, Istanbul, Turkey: proceedings". Istambul: Institute of Electrical and Electronics Engineers (IEEE), 2002, p. 149-160.