HP-UX Workload Manager User's Guide

Chapter 7 255
7 Managing SLOs across
partitions
WLM can manage SLOs across virtual partitions and nPartitions. WLM
provides a global arbiter, wlmpard, that can take input from the WLM
instances on the individual partitions. The global arbiter then moves
CPU resources (cores) between partitions, as needed to better achieve
the SLOs specified in the WLM configuration files that are active in the
partitions. These partitions can be nested—and can even contain FSS
and PSET-based workload groups. (wlmpard can be running in one of the
managed partitions or on a supported platform with network
connectivity to the managed partitions.)
The following sections describe how WLM manages SLOs across virtual
partitions and nPartitions and explains how to configure cross-partition
management.
Overview
WLM virtual partition (vPar) management migrates cores between
virtual partitions. However, with nPartitions being physical entities,
WLM nPartition management only gives the appearance of migrating
cores. This pseudo-migration is achieved—using the Instant Capacity
(iCAP) software—by deactivating cores on one nPartition then activating
cores on another nPartition.
Figure 7-1 shows WLM managing the partitions on a server. For a
detailed explanation of the figure, see “How WLM works” on page 112.