HP-UX Workload Manager overview

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– Available resources (including those after higher priority SLOs have been satisfied)
A goal-based SLO consists of:
– A workload
– A goal
– A priority
– Optional conditions (time of day, an event, and so on)
– Optional CPU lower and/or upper bounds
Prioritized SLOs
WLM enables you to prioritize the SLOs. When CPU resources are not sufficient to satisfy all SLOs,
WLM grants CPU resources to the highest priority SLOs first. After the demands of the higher priority
SLOs are satisfied, WLM grants any remaining resources to the lower priority SLOs. Valid priorities
start at 1, with 1 being the highest priority.
A single workload can have multiple SLOs, each with a different priority. One SLO would be the high-
priority, “must meet” goal, while the remaining SLOs would be lower priority, “meet if possible” goals
(stretch goals). For example, an SLO might have a priority 1 goal of maintaining an allocation of at
least two cores for a workload. Another SLO for the same workload could have a priority 2 goal to
allocate three or four cores if available when the workload becomes very busy. This lower priority
goal is met only after the priority 1 SLO for the workload and all other workloads are met.
SLO priorities do not have to be uniquely assigned—multiple SLOs can be granted the same priority,
allowing more than one workload’s objective to be top priority. This configuration can be beneficial
when more than one workload is equally important. Typically, all the SLOs in a given configuration
should not be assigned the same priority; otherwise, under a heavy system load, WLM might not be
able to allocate CPU resources effectively when there are not enough CPU resources to satisfy all
SLOs.
What is the ideal environment for HP-UX Workload
Manager?
You will benefit most from WLM if your environment meets one or more of the following conditions:
• You run more than one workload concurrently on a server. The workloads can all run under one
instance of HP-UX or in separate partitions, each with its own instance of HP-UX. These workloads
could be multiple database servers, a database server and an applications server, or any other
combination of workloads, provided that they are on PA-RISC servers (HP 9000) running HP-UX 11i
v1 or later or on PA-RISC or Intel® Itanium®-based servers running HP-UX 11i v2 (B.11.23) or
HP-UX 11i v3 (B.11.31), or later.
• You have CPU-intensive workloads that can be prioritized.
• You have an important workload with end-user performance requirements.
• You want consistent performance from applications under varying application and system loads.
• You run Serviceguard and need proper prioritization of workloads after a failover.
• You want more control over resource allocation than PRM provides.
HP-UX Workload Manager solutions
The following sections illustrate how WLM provides various business solutions. The SLOs are outlined
without including the necessary configuration file syntax (for configuration file syntax, see the
wlmconf(4) manpage or the HP-UX Workload Manager User’s Guide).