MACT: Discrete Memory Access Requests Batch Processing Mechanism for High-Throughput Many-Core Processor

The rapid development of new high-throughput applications, such as Web services, brings huge challenges to traditional processors which target at high-performance applications. High-throughput many-core processors, as new processors, become hotspot for high-throughput applications. However, with the dramatic increase in the number of on chip cores, combined with the property of memory intensive of high throughput applications, the “memory wall” problems have intensified. After analyzing the memory access behavior of high throughput applications, it is found out that there are a large proportion of fine-grained granularity memory accesses which degrade the efficiency of bandwidth utilization and cause unnecessary energy consumption. Based on this observation, in high-throughput many-core processors design, memory access collection table (MACT) is implemented to collect discrete memory access requests and to handle them in batch under deadline constraint. Using MACT hardware mechanism, both bandwidth utilization and execution efficiency have been improved. QoS is also guaranteed by employing time-window mechanism, which insures that all the requests can be sent before the deadline. WordCount, TeraSort and Search are typical high-throughput application benchmarks which are used in experiments. The experimental results show that MACT reduces the number of memory accesses requests by 49% and improves bandwidth efficiency by 24%, and the average execution speed is improved by 89%.