Memory access scheduling

The bandwidth and latency of a memory system are strongly dependent on the manner in which accesses interact with the “3-D” structure of banks, rows, and columns characteristic of contemporary DRAM chips. There is nearly an order of magnitude difference in bandwidth between successive references to different columns within a row and different rows within a bank. This paper introduces memory access scheduling, a technique that improves the performance of a memory system by reordering memory references to exploit locality within the 3-D memory structure. Conservative reordering, in which the first ready reference in a sequence is performed, improves bandwidth by 40% for traces from five media benchmarks. Aggressive reordering, in which operations are scheduled to optimize memory bandwidth, improves bandwidth by 93% for the same set of applications. Memory access scheduling is particularly important for media processors where it enables the processor to make the most efficient use of...

• Type: Conference
• Year: 2000
• Where: ISCA
• Authors: Scott Rixner, William J. Dally, Ujval J. Kapasi, Peter R. Mattson, John D. Owens
• Keywords: Hardware, Improves Bandwidth, ISCA 2000, Memory Access Scheduling, Memory Bandwidth