IBM pSeries690 Personal Computer User Manual


 
You can have more than one profile for a partition. However, you can only activate a
partition with one profile at a time. Additionally, affinity partitions and logical partitions
cannot be active at the same time.
When you create a partition profile, the HMC shows you all the resources available on
your system. The HMC does not, however, verify if another partition profile is currently
using a portion of these resources. For example, the HMC might show 16 processors
on your system, but does not notify you that other partitions are using nine of them. You
can create two partition profiles, each using a majority of system resources. If you
attempt to activate both of these partitions at the same time, the second partition in the
activation list fails.
System Profiles
Using the HMC, you can create and activate often-used collections of predefined
partition profiles. A collection of predefined partition profiles is called a system profile.
The system profile is an ordered list of partitions and the profile that is to be activated
for each partition. The first profile in the list is activated first, followed by the second
profile in the list, followed by the third, and so on.
The system profile helps you change the managed systems from one complete set of
partitions configurations to another. For example, a company might want to switch from
using 12 partitions to using only four, every day. To do this, the system administrator
deactivates the 12 partitions and activates a different system profile, one specifying four
partitions.
When you create a group of affinity partitions, the HMC automatically creates a system
profile that includes all of the affinity partitions that you created.
Types of Partitions
The HMC allows you to use two types of partitions: logical partitions and the full system
partition.
Logical Partitions
Logical partitions are user-defined system resource divisions. Users determine the
number of processors, memory, and I/O that a logical partition can have when active.
Affinity Partitions:
An affinity partition is a special type of logical partition in which
processors and system memory are allocated in a predefined way that may increase
performance when running some types of applications (memory is assigned to a
processor that is in close physical proximity to it).
Affinity partitions can be created with either four or eight processors. The user
determines the allocation of I/O resources in a server with affinity partitions; only the
allocation of processors and memory is predefined.
Reassigning Partition Resources Dynamically:
You can logically attach and detach
a managed system’s resources to and from a logical partition’s operating system
4 Eserver pSeries 690 User’s Guide