HP Integrity NonStop J-Series - Manual (Page 114)

Guardian Performance Analyzer (GPA) User Guide
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Implementing GPA Tuning
Recommendations
On the basis of its analysis, GPA makes the following kinds of explicit tuning
recommendations:

Moving primary disk processes to correct a load imbalance on the node.

Resetting disk cache allocations to improve cache hit performance and/or reduce
disk queuing.

Moving processes among CPUs to relieve a detected memory shortage problem or
to correct a processor utilization imbalance.

Reconfiguring the number of disk subprocesses associated with a logical volume.
Note that in making each tuning recommendation for a given run, GPA takes into account
the effect on the system of all previous tuning recommendations for that run. In this
way, GPA is able to issue multiple tuning recommendations in a single analysis.
You can implement the GPA recommendations for moving primary disk processes and
resetting cache allocations simply by running PUP or SCF using the PUPIN or SCFIN
file as input. Note that you must be a super group user to do this. PUPIN contains the
PUP PRIMARY and PUP SETCACHE commands required to perform the
corresponding tuning operations. SCFIN contains the SCF PRIMARY and SCF ALTER
DISK, CACHE commands required to perform the corresponding tuning operations.
If, after running PUPIN/SCFIN, you want to restore the system to its previous state, you
can do so by running PUP or SCF using PUPBAK or SCFBAK as the input file. After
implementing the GPA tuning recommendations, you should remeasure the system
and run another GPA analysis.
Beyond the GPA tuning recommendations, you can take these steps to deal with system
performance problems:

Check applications for possible bottlenecks.

Examine the data communications environment for sources of trouble.

Analyze the system hardware to determine if it provides an optimum configuration.
For system tuning, you need to keep in mind that GPA is meant to serve mainly as a guide
and to provide a quick and convenient performance analysis. For the best long-term
solutions to system performance problems, you need to have properly trained
personnel do a careful and detailed analysis.
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