Introduction to Workload Partitions (WPAR) Technology in AIX 6

Overview of partitioning and virtualization
capabilities prior to AIX6
Today’s competitive corporate environment requires nimble IT departments with
the abilty to respond quickly to changes in the capacity and the use of innovative
methods to reduce time to market for new applications and systems. Escalating
costs of power, raised floor capacity and administrative costs also drive the need
to utilize technology in new ways to maximize a company’s IT investment.
Figure 1-1 on page 5 presents the various partitioning and virtualization
technologies that have been integrated within AIX. Of the different technologies
presented in Figure 1-1, Workload Manager (WLM) is the only one that is
software based.

AIX Workload Manager
Within AIX, Workload Manager has been part of the Operating System since
version 4.3. It allows multiple workloads to run under one AIX instance. The
system administrator builds rules based upon a user, process, or workload.
Based upon these rules, shares of CPU and/or memory would adjust to the
workload with peak demand.
If you have used Workload Manager in the past, then Chapter 7, “Resource
Control” on page 233 will be of interest to you to see the relationship between
Workload Manager and Workload Partitions.
Logical Partitions
With AIX 5.1 and POWER4™ technology IBM announced Logical Partitions
(LPARs) as a way to provide greater flexibility and better utilization of large
systems. Now systems could run AIX and Linux® in separate partitions starting
at a minimum of 1 CPU, 1 GB of memory and 1 ethernet adapter. However, a
reboot was required to move resources between LPARs.
Dynamic Logical Partitions
AIX 5.2 added more systems flexibility by being able to move CPU, I/O adapters
& memory dynamically without rebooting the LPARs. The combination of
firmware, hypervisor, and AIX are the technologies that together supported this
innovation. It allowed IT environments to become more adaptable to their
customers’ needs.
Advanced POWER Virtualization
AIX 5.3’s and POWER5™’s ability to virtualize CPUs, share ethernet adapters,
and virtually slice disks for provisioning to client LPARs has IT environments
impressing their customers and upper management. Virtualization is an excellent
vehicle to address business needs while controlling costs and IBM’s System p
Advanced Power Virtualization (APV) offers advanced technology to facilitate
server consolidation, reduce costs, provide redundancy, and adapt capacity to
quickly meet demand. APV can be used to reduce the need for static adapters,
can rapidly respond to increasing capacity demands and generally allows
companies to utilize their purchasing dollars more effectively.
From this history of improving flexibility of system resources, we now have AIX 6.
AIX 6 is capable of running on POWER4, POWER5, POWER5+, PPC970, and
POWER6™-based servers.