基于龙芯CPU的多核全系统模拟器SimOS-Goodson

SimOS-Goodson:A Goodson-Processor Based Multi-Core Full-System Simulator

随着片上多核结构成为当前高性能微处理器发展的趋势,目标工作负载也变得多样化,传统的用户级模拟器已不能适应未来体系结构的研究需要.基于SimOS全系统模拟环境,设计并实现了龙芯CPU的片上多核全系统模拟器SimOS-Goodson.在SimOS-Goodson的设计中运用了时序与功能分离的组织形式,并采用了一种新的值预测校验算法来解决模拟环境中的存储一致性问题.经过与真实硬件环境进行交叉校正,保证了模拟器的可信度与准确度.与用户级模拟器相比,SimOS-Goodson保持了高速、灵活的优点,又具备精确、全系统和易使用的特征.通过对完整Linux操作系统的移植,可在SimOS-Goodson所模拟的全系统环境中进行各类微体系结构和应用负载的分析与评估.在3.0GHz的Pentium4微机上,SimOS-Goodson的指令模拟速度超过300K/秒.SimOS-Goodson将会在基于龙芯CPU的片上多核体系结构研究中发挥重要作用.

As the Chip MultiProcessors （CMPs） have become the trend of high performance microprocessors, the target workloads become more and more diversified. The traditional user-level simulators cannot handle them, so new simulators are needed for the future architecture research. Based on the SimOS full-system environment, a new multi-core full-system simulator of Goodson processors, SimOS-Goodson, has been designed and implemented. The SimOS-Goodson decouples the simulation functionality and timing. It adopts a new value-prediction approach to implement memory consistency in the simulation environment. The credibility and accuracy of SimOS-Goodson are achieved by cross-validating the simulator with the actual hardware. The simulator inherits the benefits such as high speed and high flexibility from the traditional user-level simulators. It also has the new benefits such as accuracy, full-system support and easy to use. By porting the entire Linux OS, analysis and evaluation of the microarchitecture and workloads can be conducted easily in the SimOS-Goodson full-system environment. On a machine of Pentium4 3.0GHz, the speed of SimOS-Goodson exceeds 300K instructions per second. SimOS-Goodson will play a key role in the research of future Goodson multi-core architecture.