partitioning enables users to configure a single computer into several independent systems. each of these systems, called logical partitions, is capable of running applications in its own independent environment. this independent environment contains its own operating system, its own set of system processors, its own set of system memory, and its own i/o adapters.

    the hmc allows you to perform many hardware management tasks for your managed system, including configuring logical partitions. you can choose to operate your managed system as a single server (called full system partitions), or you can choose to run multiple partitions.

    partition profiles

    a profile defines a configuration setup for a managed system or partition. the hmc allows you to create multiple profiles for each managed system or partition. you can then use the profiles you created to start a managed system or partition in a particular configuration.

    a partition does not actually own any resources until it is activated; resource specifications are stored within partition profiles. the same partition can operate using different resources at different times, depending on the profile you activate.

    when you activate a partition, you enable the system to create a partition using the set of resources in a profile created for that partition. for example, a logical partition profile might indicate to the managed system that its partition requires 3 processors, 2 gigabytes of memory, and i/o slots 6, 11, and 12 when activated.

    you can have more than one profile for a partition. however, you can only activate a partition with one profile at a 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 eight processors on your system, but does not notify you that other partitions are using six 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 partition configurations to another. for example, a customer may want to switch from using 8 partitions to using only four, every day. to do this, the system administrator deactivates the 8 partitions and activates a different system profile, one specifying four partitions.

    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.

    full system partition: a special partition called the full system partition assigns all of your managed system’s resources to one large partition. the full system partition is similar to the traditional, non-partitioned method of operating a system. because all resources are assigned to this partition, no other partitions can be started when the full system partition is running. likewise, the full system partition cannot be started while other partitions are running.

    for more detail on partitions, see the hardware management console for pseries installation and operations guide.