GPA Manual

Introducing GPA
Guardian Performance Analyzer (GPA) Manual—135081
1-3
How GPA Works
The GPA module is essentially a model of a Tandem node. In performing its analysis,
GPA breaks the system down into the following subsystems: CPU, memory, disk
volume, and disk cache. GPA then assesses the performance of the system as a whole
and also separately analyzes each subsystem with respect to a number of relevant
performance parameters such as CPU utilization, disk volume queuing, cache hit
percentage, and so on. The module processes the formatted data files in accordance with
the model and uses the text formats contained in the TUNEDATA file to generate the
GPA standard textual reports.
PUPIN is a PUP INPUT file that can be run to tune the system according to some of the
GPA recommendations. The file contains PUP PRIMARY and PUP SETCACHE
commands. The PRIMARY commands are used to move primary disk processes among
the CPUs in the system in order to help balance the load on the CPUs. The SETCACHE
commands are used to redistribute the cache allocations for the volumes to improve the
operating efficiency of the system.
Figure 1-1. How GPA Works
MEASFH
TUNEDATA
PUPIN /
SCFIN
PUPBAK /
SCFBAK
OBEYTUNE
Optional
Standard
Errors
#OUT
Measure
Data
GPA
DISCCPU PROCESS
001CDT .CDD