Chinese Journal of Computers   Full Text
Title	Design of the Simultaneous Multithreading Godson-2 Processor
Authors	LI Zu-Song1),2) XU Xian-Chao1),2) HU Wei-Wu1) TANG Zhi-Min1)
Address	1)(Key Laboratory of Computer System and Architecture, Institute of Computing Technology, Chinese Academy of Sciences, Beijing 100190) 2)(Graduate University of Chinese Academy of Sciences, Beijing 100039)
Year	2009
Issue	No.11(2265—2273)
Abstract &   Background	Abstract A design model and microarchitecture implement scheme of simultaneous multithreading Godson-2 processor is proposed in this paper. The operating system on simultaneous multithreading Godson-2 processor is designed for operating multiple individual threads simultaneously and improving system level performance. Linux operating system is booted in simultaneous multithreading Godson-2 processor and application programs such as SPEC CPU2000 are executed in it to evaluate performance. It has been shown that simultaneous multithreading Godson-2 processor improves the performance of superscalar Godson-2 significantly by full exploitation of instruction-level parallelism. The average speedup is 31.1%. Keywords Godson-2; simultaneous multithreading; microarchitecture; Linux operating system Background With Moore’s law furnishing chip designers with billions of transistors, architects are increasingly moving towards simultaneous multithreading(SMT) and chip multiprocessors(CMP) as an effective way of dealing with escalating design complexity and power constraints and exploiting thread level parallelism to improve the performance using available on-chip transistor resources. General purpose processor Godson-2 is developed by the Institute of Computing Technology, Chinese Academy of Sciences. Superscalar Godson-2 processor can only exploits instruction-level parallelism and data-level parallelism. Developing from conventional instruction-level parallelism and data-level parallelism to thread-level parallelism by implementing multithread technique can improve performance of Godson-2 significantly. Nowadays, there is a clear thread in industry towards CMP+SMT processors, like the Intel Core 2 Duo, IBM POWER5, and POWER6, and SUN T1 and T2 Niagara processors. Godson-3 Processor implements CMP technique. And the work demonstrated in this paper of Godson-2 multithreading processor has been implemented to exploit thread-level parallelism fully by SMT technique. The work is supported by the National Natural Science Foundation of China(60325205, 60703017 and 60736012), the National High Technology Research and Development Program(863 Program) of China(2007AA01Z114), the National Basic Research Program(973 Program) of China(2005CB321600).