Game-tree search plays an important role in the field of Artificial Intelligence (AI). In this paper, we characterize one parallel game-tree search workload in chess: the latest version of Crafty, a state of art pr...Game-tree search plays an important role in the field of Artificial Intelligence (AI). In this paper, we characterize one parallel game-tree search workload in chess: the latest version of Crafty, a state of art program, on two Intel Xeon shared-memory multiprocessor systems. Our analysis shows that Crafty is latency-sensitive and the hash-table and dynamic tree splitting used in Crafty cause large scalability penalties. They consume 35%-50% of the running time on the 4-way system. Furthermore, Crafty is not bandwidth-limited.展开更多
Recently, a method known as pipeline stage unification (PSU) has been proposed to alleviate the increasing energy consumption problem in modern microprocessors. PSU achieves a high energy efficiency by employing a c...Recently, a method known as pipeline stage unification (PSU) has been proposed to alleviate the increasing energy consumption problem in modern microprocessors. PSU achieves a high energy efficiency by employing a changeable pipeline depth and its working scheme is eligible for a fine control method. In this paper, we propose a dynamic method to study fine-grained program interval behaviors based on some easy-to-get runtime processor metrics. Using this method to determine the proper PSU configurations during the program execution, we are able to achieve an averaged 13.5% energydelay-product (EDP) reduction for SPEC CPU2000 integer benchmarks, compared to the baseline processor. This value is only 0.14% larger than the theoretically idealized controlling. Our hardware synthesis result indicates that the proposed method can largely decrease the hardware overhead in both area and delay costs, as compared to a previous program study method which is based on working set signatures.展开更多
文摘Game-tree search plays an important role in the field of Artificial Intelligence (AI). In this paper, we characterize one parallel game-tree search workload in chess: the latest version of Crafty, a state of art program, on two Intel Xeon shared-memory multiprocessor systems. Our analysis shows that Crafty is latency-sensitive and the hash-table and dynamic tree splitting used in Crafty cause large scalability penalties. They consume 35%-50% of the running time on the 4-way system. Furthermore, Crafty is not bandwidth-limited.
基金supported by VLSI Design and Education Center (VDEC),University of Tokyo with the collaboration with Synopsys Corporation
文摘Recently, a method known as pipeline stage unification (PSU) has been proposed to alleviate the increasing energy consumption problem in modern microprocessors. PSU achieves a high energy efficiency by employing a changeable pipeline depth and its working scheme is eligible for a fine control method. In this paper, we propose a dynamic method to study fine-grained program interval behaviors based on some easy-to-get runtime processor metrics. Using this method to determine the proper PSU configurations during the program execution, we are able to achieve an averaged 13.5% energydelay-product (EDP) reduction for SPEC CPU2000 integer benchmarks, compared to the baseline processor. This value is only 0.14% larger than the theoretically idealized controlling. Our hardware synthesis result indicates that the proposed method can largely decrease the hardware overhead in both area and delay costs, as compared to a previous program study method which is based on working set signatures.