Accelerating Data Transfer in Dataflow Architectures Through a Look-Ahead Acknowledgment Mechanism  

作　　者：Yu-Jing Feng De-Jian Li Xu Tan Xiao-Chun Ye Dong-Rui Fan Wen-Ming Li Da Wang Hao Zhang Zhi-Min Tang 冯煜晶;李德建;谭旭;叶笑春;范东睿;李文明;王达;张浩;唐志敏(State Key Laboratory of Computer Architecture,Institute of Computing Technology,Chinese Academy of Sciences,Beijing 100190,China;Beijing Smartchip Microelectronics Technology Company Limited,Beijing 100000,China;School of Computer and Control Engineering,University of Chinese Academy of Sciences,Beijing 100190,China)

机构地区：[1]State Key Laboratory of Computer Architecture,Institute of Computing Technology,Chinese Academy of Sciences,Beijing 100190,China [2]Beijing Smartchip Microelectronics Technology Company Limited,Beijing 100000,China [3]School of Computer and Control Engineering,University of Chinese Academy of Sciences,Beijing 100190,China

出　　处：《Journal of Computer Science & Technology》2022年第4期942-959,共18页计算机科学技术学报（英文版）

基　　金：This work was supported by the Project of the State Grid Corporation of China in 2020"Integration Technology Research and Prototype Development for High End Controller Chip"under Grant No.5700-202041264A-0-0-00.

摘　　要：The dataflow architecture,which is characterized by a lack of a redundant unified control logic,has been shown to have an advantage over the control-flow architecture as it improves the computational performance and power efficiency,especially of applications used in high-performance computing(HPC).Importantly,the high computational efficiency of systems using the dataflow architecture is achieved by allowing program kernels to be activated in a simultaneous manner.Therefore,a proper acknowledgment mechanism is required to distinguish the data that logically belongs to different contexts.Possible solutions include the tagged-token matching mechanism in which the data is sent before acknowledgments are received but retried after rejection,or a handshake mechanism in which the data is only sent after acknowledgments are received.However,these mechanisms are characterized by both inefficient data transfer and increased area cost.Good performance of the dataflow architecture depends on the efficiency of data transfer.In order to optimize the efficiency of data transfer in existing dataflow architectures with a minimal increase in area and power cost,we propose a Look-Ahead Acknowledgment(LAA)mechanism.LAA accelerates the execution flow by speculatively acknowledging ahead without penalties.Our simulation analysis based on a handshake mechanism shows that our LAA increases the average utilization of computational units by 23.9%,with a reduction in the average execution time by 17.4%and an increase in the average power efficiency of dataflow processors by 22.4%.Crucially,our novel approach results in a relatively small increase in the area and power consumption of the on-chip logic of less than 0.9%.In conclusion,the evaluation results suggest that Look-Ahead Acknowledgment is an effective improvement for data transfer in existing dataflow architectures.

关 键 词：dataflow model control-flow model high-performance computing application data transfer power efficiency 

分 类 号：TP3[自动化与计算机技术—计算机科学与技术]