Virtage: Server virtualization with hardware transparency

Abstract

This paper presents Virtage, Hitachi's virtualization technology, which enables logical partitioning of server platforms. Logical partitioning architecture brings two benefits to this virtualization technology, one is hardware transparency and another is better performance. We first describe its key feature: hardware transparency. With the advantage of hardware transparency for logical servers, it is possible to provide the same guest Operating System (OS) interface from both physical servers (non-virtualized servers) and logical servers. Virtage is hypervisor-type virtualization, and therefore has a natural performance advantage over host-emulation virtualization offerings because guest OSs can be simply and directly executed on the virtualized environment without host intervention. Then we demonstrate this lower overhead for CPU and I/O with performance experiments and explain how Virtage brings mainframe-class virtualization to blade servers. In this paper we study the factors of virtualization overhead for CPU and I/O by using original event monitoring tool that can get hypervisor-event information. © 2010 Springer-Verlag.