Research On Cooperative Cache Within Virtual Machines Based On Multiprocessor Platform

With the fast development of VLSI,the available on-chip transistors resources is becoming more and more. The basic problem we face is how to make the best use of the transistors resources. As the appearance of chip multiprocessor, we can fully utilize the transistors resources to improve the performance of processor. However, with the emergence of multiprocessor some new problems have arisen. The competition of limited cache resources and bandwidth resources will further increase the system pressure when access memories, so we need to develop an effective management strategy that will help enhance the performance of the system. The multiprocessor platform also has the problem of without enough multiprocessor software, so it affects the overall performance of multiprocessor platform. Therefore, we proposed virtualization technology to improve the utilization of hardware resources.The virtualization has many advantages which make virtualization developed rapidly and became a hot topic. This paper first present a brief introduction of Cache technology, and then it focus on the L2 cache management strategy. After that,we introduce the concept of virtualization and the implementation of virtualization. Finally, we design and implement the cooperative cache within virtual machines. For that goal, the research content and achievement include:(1)To study the cooperative cache within virtual machines, we need to find a multiprocessor simulator which support virtualization (focus on CPU and memory). However, most of the simulators which support virtualization are all full-system. And most of them have really complicated state and code space, and therefore lead to rather slow simulation speed. In this paper we present a parallel user-level simulator, PVMsim. It can simulate a virtual simulation environment for users who study virtualization. (2)We research the advantages and disadvantages of L2 Cache management strategy on multiprocessor platform. On this basis, we first design the hardware structure of cooperative cache, and then we design the special implementation strategy of cooperative cache, at last we introduce the working mechanisms of cooperative cache. (3)On the basis of shared L2 cache and cooperative cache within virtual machines, we use the SPLASH-2 to test the performance of simulator in different L2 cache configuration. The result shows that the cooperative cache within virtual machines has the advantages of low memory access latency, high hit rate, and good scalability.