HP-UX Workload Manager User's Guide

Configuring WLM
Trying a configuration without affecting the system
Chapter 5 239
Figure 5-8 Passive WLM operation
Thus, in passive mode, WLM takes in data on the workloads. It even
forms a CPU request for each workload based on the data received.
However, it does not change the CPU allocations for the workloads on the
system.
Effect of mincpu and maxcpu values
In passive mode, WLM does use the values of the following keywords to
form shares requests:
• mincpu/maxcpu
• gmincpu/gmaxcpu
• hmincpu/hmaxcpu
However, because WLM does not adjust allocations in passive mode, it
may appear that these values are not used.
Monitoring WLM in passive mode
Use the wlminfo utility to monitor WLM in passive mode. Its output
reflects WLM behavior and operation. It shows how much CPU WLM is
requesting for a workload—given the workload’s current performance.
However, because WLM does not actually adjust CPU allocations in
passive mode, WLM does not affect the workload’s performance—as
reported in usage values and metric values. Once you activate WLM in
normal mode, it adjusts allocations and affects these values.
For the purposes of passive mode, WLM creates a PRM configuration
with each of your workload groups allocated one CPU share, and the rest
going to the reserved group PRM_SYS. (If your configuration has
PSET-based workload groups, the PSETs are created but with zero CPU
resources.) In this configuration, CPU capping is not enforced—unlike in
normal WLM operation. Furthermore, this configuration will be the only
one used for the duration of the passive mode. WLM does not create new
PRM configurations to change resource allocations. Consequently, do not
System activity
WLM
Usage/metrics