Version 3.1-en Solaris 10 Container Guide - 3.1 2. Functionality Effective: 30/11/2009
2.2.5. Summary of virtualization technologies
[ug] The virtualization technologies discussed above can be summarized in the following table –
compared to installation on a separate computer.
Separate
computer
Domains/
Physical
partitions
Logical
partitions
Containers
(Solaris zones)
in an OS
Consolidation in
one computer
Separation + O +(Software)
- (Hardware)
+ (Software)
- (Hardware)
-
Application + + + + -
SW maintenance - - - + O
HW maintenance + + O O O
Delegation - - - + -
Scalability O + O + +
Overhead - - - + +
OS versions one each several several one one
Table 2: [ug] Summary of virtualization technologies
Key for the meaning of the symbols:
•+ good
•O is neither good nor bad
•- means: has disadvantages
While separation is of course best in a stand-alone computer. Physical partitions use the same
cabinet with shared power supplies (fire can harm each partition), although the partitions are
independent. Lpars, LDom and containers are separated in the OS environment only.
Consolidation in an operating system reveals all that is visible in the applications to each application.
In all other cases, applications are separated.
Unified SW maintenance can only be performed with zones and consolidation in one computer. The
other technologies require multiple maintenance.
HW maintenance on the machine of the application is practicable only for domains or separate
computers without affecting other applications, unless mobile Lpars/LDom or cluster technologies with
flying zones are used.
The delegation of portions of administrative tasks is possible for containers only. All other
technologies require that the tasks be defined exactly and that dedicated roles are assigned. This is
costly and time-consuming.
Scalability for separate computers and Lpars is limited based on the hardware (defined performance
of the shared interconnect) while domain capacity can be customized by additional hardware.
Containers and consolidation on one computer run without adaption of the application on bigger
computers. Additional reserves can be used by relocating additional containers to this computer.
Overhead is higher for separate computers and physical and logical partitioning because one
operating system with CPU and memory requirements runs per application. Containers and
consolidation on one computer share one operating system and are therefore considerably more
economical with regard to their consumption of resources. The lower the resource requirements of an
application, the more pronounced the effect.
The OS version of each operating system installation must be maintained separately. This means
overhead. Therefore, for separate computers as well as physical and logical virtualization, more effort
must be expended than for containers or consolidation on one computer. However, multiple OS
versions enable the use of different versions of the OS if required by the applications. The
assessment in this regard depends on data center policies and operation purposes.
The overhead of several OS instances can be reduced by using management software such as
e.g. Sun xVM OpsCenter, which requires a certain investment.
14