This field displays the number of BSR arrays that are currently assigned to the logical partition.
The BSR is a memory register that is located on certain processors. A parallel-processing application can use a BSR to perform barrier synchronization, which is a method for synchronizing the threads in the parallel-processing application.
On logically partitioned systems, BSRs are divided into arrays. You can assign BSR arrays to partition profiles. Each BSR array is eight bytes long. The number of BSR arrays that are available on a managed system depends on the number and type of processors used on the server model. You can see the number of BSR arrays that are available on a managed system by viewing managed system properties.
You can assign BSR arrays only to logical partitions that use dedicated processors. Also, not all operating system versions supports use of the BSR. For information on whether your operating system supports use of the BSR, consult your operating system documentation.
This value is set in the active partition profile at the time that you used the partition profile to activate the logical partition. To change this value, shut down and restart the logical partition using a partition profile with a different value.