Solaris Operating System Hardware Virtualization Product Architecture 
by Chien-Hua Yen
November, 2007
Although the concept of virtualization is not new, virtualization has recently become a well-accepted means to consolidate servers and reduce the costs of hardware acquisition, energy consumption, and space utilization. Server virtualization can be implemented at different levels on the computing stack, including the application level, operating system level, and hardware level. Hardware level virtualization allows a system to run multiple OS instances; with less sharing of system resources than OS level virtualization, hardware virtualization provides stronger isolation of operating environments. Hardware virtualization has become popular because of increasing CPU power and low utilization of CPU resources in the IT data center.
This blueprint provides a comprehensive examination of hardware virtualization, particularly as it applies to Sun platforms. It explores the underlying hardware architecture and software implementation. Great emphasis has been placed on the CPU hardware architecture limitations for virtualizing CPU services and their software workarounds, with details on the software architecture for implementing three types of virtualization: CPU virtualization, Memory virtualization, and I/O virtualization. It examines three important implementations in detail: Sun xVM Server, Logical Domains, and VMware's relevant products, culminating in a comprehensive comparison of these important solution.
