关键词: 虚拟机管理器, 虚拟机监视器, 远程磁盘缓存, 内存服务器

Abstract:

Abstract: In virtual machine systems, with the increase in the number of virtual machines and the demands of appli-cations, the main memory is becoming a bottleneck of application performance. To improve paging performance for memory-intensive or I/O-intensive workloads, this paper proposes the remote disk cache (REMOCA), which allows a virtual machine to use the memory resource on other physical machines as its cache between its virtual memory and virtual disk devices. The goal of REMOCA is to reduce disk access, which is much slower than transferring memory pages over modern interconnect networks. As a result, the average disk I/O latency can be improved. REMOCA is implemented within the virtual machine monitor, by intercepting guest events such as page evictions and disk accesses. This design is transparent to the applications, and is compatible with existing techniques like ballooning and ghost buffer. Moreover, a combination of them can provide a more flexible resource management policy. The experimental results show that REMOCA can efficiently alleviate the impact of thrashing behavior, and also significantly improve the performance for real-world I/O-intensive applications.

Key words: virtual machine monitor(VMM), Xen, remote disk cache (REMOCA), memory server