Performance evaluation of distributed systems

近年来，已经给予相当大的关注，组织计算资源在数据中心作为一个共同的基础设施，由多个应用程序共享。每个应用程序都有自己的工作负载和性能目标。工作量是随时间变化的，因为用户的需求可能会随着时间的推移而变化。在管理数据中心的资源时，一个重要的考虑因素是实现有效的资源利用率和满足各个应用程序的性能目标的高概率。虚拟化技术可用于提高资源管理的灵活性。应用程序部署在虚拟机上，虚拟机在物理资源上实现。通过将这些资源动态分配给虚拟机，系统可以适应不断变化的工作负载，并为各个应用程序提供良好的性能。

In recent years, considerable attention has been given to organizing the computing resources in a data centre as a common infrastructure to be shared by multiple applications. Each application has its own workload and performance goal. The workload is time-varying because the demand from users may change over time. In managing the resources in a data centre, an important consideration is to achieve efficient resource utilization and high probability of meeting the performance goal of individual applications. Virtualization technology can be used to improve flexibility in resource management. Applications are deployed on virtual machines which are implemented on physical resources. By dynamically allocating these resources to virtual machines, the system can adapt to changing workloads and provide good performance to individual applications.