The virtualization models are described by means of the following competing characteristics:
The amount of execution environment isolation
The amount of resource flexibility
The more isolation that a model provides, the less resource flexibility it provides. The more resource flexibility that a model provides, the less isolation it provides. Because these characteristics compete, they cannot be maximized by a single model.
You can use the Oracle Solaris 11.2 OS with one or more of the following virtualization technologies to maximize workload density:
Operating system (OS) virtualization provides one or more isolated execution environments in a single OS instance. Each environment contains what appears to be a private copy of the OS in a container. The OS virtualization model provides near-native performance and flexibility, and has a much smaller disk, RAM, and CPU footprint than either virtual machines or physical domains. However, the OS virtualization model provides the least amount of execution environment isolation.
Oracle Solaris 11.2 provides this virtualization model by means of the Oracle Solaris Zones product.
Virtual machines can be used to run multiple OS instances with a single set of hardware resources. Each virtual machine that you create runs its own OS. You can run various operating systems in this way. A software or firmware hypervisor creates the illusion that each guest OS instance is running on its own separate system. Virtual machines provide less resource flexibility than a machine that uses OS virtualization, but virtual machines do provide more isolation.
Oracle Solaris 11.2 provides this virtualization model by means of Oracle VM Server for SPARC, Oracle VM Server for x86, and Oracle VM VirtualBox. Note that an Oracle Solaris system on x86 might panic if Oracle VM VirtualBox and Oracle Solaris Kernel Zone are run at the same time on the system.
For information about using Oracle VM VirtualBox, see the Oracle VM VirtualBox documentation.
Hardware partitions, also known as physical domains, provide physical separation between the running OS and its separate set of resources and power. Because this model does not use a hypervisor, it provides bare-metal performance. This virtualization model provides the most isolation, but it is much less flexible with resource configuration than either the virtual machines or OS virtualization model.
Oracle provides this type of virtualization on Oracle's Sun SPARC Enterprise M-Series servers. For more information, see the Oracle SPARC M-Series Server documentation.