HP-UX System Administrator's Guide: Overview

Workload Manager (WLM)
The Process Resource Manager allows you to manually dedicate resources to specific
applications. However, many factors are likely to change constantly, such as system
load, resource utilization, resource needs, and the mix of applications that are running
at any given time. If the conditions and needs of your server environment are constantly
changing, WLM can continuously monitor and adjust resources to maintain application
performance and business goals.
Technology Summary
Workload Manager (WLM) is an automatic resource management tool used for
goal-based workload management. A workload is a group of processes that are treated
as a single unit for the purposes of resource allocation. For example, a database
application that consists of multiple cooperating processes could be considered a
workload.
WLM provides automatic resource allocation and application performance management
through the use of prioritized Service Level Objectives (SLOs). Multiple prioritized
workloads can be managed dynamically on a single server based on their reported
performance levels.
WLM manages workloads as defined in a configuration file. You assign applications
and users to workload groups. WLM automatically allocates processing core resources
to achieve the desired SLO. WLM can manage real memory and disk bandwidth but
not in response to SLOs. With real memory, WLM allows you to specify lower and
upper limits on the amount of memory a workload receives. You can statically assign
disk bandwidth shares. If multiple users or applications within a workload are
competing for resources, standard HP-UX resource management determines the resource
allocation.
Tools to Administer/Configure
The Workload Manager can be configured manually using a configuration file and
WLM commands, interactively using the WLM configuration wizard, or by using the
WLM graphical user interface.
28 HP-UX Virtualization Technologies