Chapter 4. Changing Logical Partition Processing Resources; Changing Logical Partition Interactive Performance - IBM AS/400e Manual

Chapter 4. Changing logical partition processing resources

You can designate processing resources to increase or decrease the performance capabilities of your
logical partitions. Processing resources include interactive performance percentage, processors, main
storage, and OptiConnect.
You can adjust the configuration of a partition to fit the performance you assign to it. You can accomplish
this by removing processing resources from one logical partition and adding them to another. This will
optimize performance for the logical partitions that carry the most performance.
When you add or remove processing resources remember the following:
v You can only change processing resources from the primary partition.
v You can change interactive performance percentage, processors, and main storage in the Change
Partition Processing Resources display.
v Activating changes to processing resources might require a system IPL.
v The sum of each of the processing resources across the logical partitions cannot exceed that of the
system. In other words if you have a total of four processors, you cannot assign three to the primary
partition and two to a secondary partition.
v Every logical partition must have at least one processor.
v The primary partition must have at least 256 MB of main storage. Secondary partitions must have at
least 64 MB of main storage.
v When you change processing resources, you can designate upper and lower limits. In other words, you
can specify that a logical partition can only have a maximum or minimum amount of main storage,
processors, and interactive performance. By setting limits, you activate changes in logical partition
processing resources with a logical partition IPL instead of a system IPL.
The following pages will show you how to change these resources:
v Changing logical partition interactive performance
v Changing logical partition main storage
v Changing logical partition processors

Changing logical partition interactive performance

Applications that interact directly with a user through some sort of system workstation are interactive.
Interactive performance is a percentage of the computer's processing cycles that are dedicated to
interactive programs. You can add and remove as much interactive performance as you need from a
logical partition as long as you remember these rules:
v Each logical partition must have at least 1% of interactive performance. Depending on each system,
some logical partitions require more than 1% of interactive performance.
v The sum of the interactive performance for all logical partitions cannot exceed 100%.
v You cannot exceed the maximum or minimum limits for the secondary partition that are determined by
its processor count.
Notes:
1. To activate changes to interactive performance on secondary partitions, you need to restart the
secondary partition.
2. To activate changes to interactive performance on the primary partition, you need to restart the entire
system.
3. If you are also changing logical partition processors or main storage, wait until you have made all of
your changes before you perform the IPL. This will save time.
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