Sun Microsystems SPARC T5220 - Manual (Page 32)

30 Enterprise-Class Software Sun Microsystems, Inc.
single core, a task that would require additional software and considerable overhead in
competing architecture.
Figure 12. Sun provides parallelization and virtualization at every level of the technology stack
Corresponding layers of virtualization technology are built on top of the hypervisor as
shown in Figure 12. The strength of Sun’s approach is that all of the layers of the
architecture are fully multithreaded, from the processor up through applications that
use the fully threaded Java application model. Far from new technology, the Solaris OS
has provided multithreading support since 1992. This experience has helped to inform
technology decisions at other levels, ultimately resulting in a system that parallelizes
and virtualizes at every level. In addition to the processor and hypervisor, Sun provides
fully multithreaded networking and the fully multithreaded ZFS file system. Sun Logical
Domains (LDOMs), Solaris Containers, and multithreaded applications are able to
receive exactly the resources they need.
Sun Logical Domains
Supported in all Sun servers utilizing CMT technology, Sun Logical Domains provide full
virtual machines that run an independent operating system instance, and contain
virtualized CPU, memory, storage, console, and cryptographic devices. Within the Sun
Logical Domains architecture, operating systems such as the Solaris 10 OS are written
to the hypervisor, which provides a stable, idealized, and virtualizable representation of
the underlying server hardware to the operating system in each Logical Domain. Each
Logical Domain is completely isolated, and the maximum number of virtual machines
created on a single platform relies upon the capabilities of the hypervisor, rather than
the number of physical hardware devices installed in the system. For example, the Sun
SPARC Enterprise T5220 server with a single UltraSPARC T2 processor supports up to 64
logical domains
1
, and each individual logical domain can run a unique OS instance.
1.Though possible, this practice is not a generally recommended.
Storage: ZFS Virtualization
Applications
Multi-threaded Networking
Hypervisor: Multi-threaded
Chip Multithreading:
Multi-core/Multi-thread
LDOM LDOM LDOM
Container Container Container Container Container Container
Multithreading
at all layers