CP6100 I/O Process Programming Manual

Using CP6100: Managing Lines
HOW TO MEASURE PERFORMANCE. To measure the performance of
lines and create an efficient configuration, you use three
Tandem products:
1. Use XRAY to measure the lines, I/O processes, and
applications.
2. Use CMI to make provisional configuration changes.
3. Repeat steps 1 and 2 until you are pleased with the
results.
4. Modify the SYSGEN configuration file and run INSTALL.
For details about these products, consult the manuals that
describe them.
WHEN TO MEASURE. It is best to measure lines periodically,
rather than wait for dramatic changes in application performance.
On a regular schedule, take a measurement when traffic is normal,
and another measurement when traffic is at its peak. Compare the
measurements over time; has performance changed noticeably since
the last time you checked it? Before you add new lines or
devices, take measurements to help you decide where to place the
new additions to the system. After you install a new application
or system software release, take a measurement to see whether
tuning is advisable.
WHAT TO MEASURE. To find the throughput of lines and the
overhead for controlling them, include the following entities in
your XRAY configuration file:
• In the DEVICES section, include the names of the lines you
want to measure.
• In the PROGRAMS section, include the names of the I/O
processes and application processes. (For the name of a
CP6100 I/O process, give the name of any line it controls.)
Use XRAYCOM to start the measurement.
October 1985
3-22