HP OpenVMS Version 8.3 Upgrade and Installation Manual > Chapter 7 After Installing or Upgrading the OpenVMS Operating
Running AUTOGEN to Tune the System
When you install or upgrade the OpenVMS operating system,
the system executes the AUTOGEN.COM procedure to set the values
of system parameters and the sizes of the page, swap, and dump files
according to the system configuration.
After running your system for at least 24 hours with users
or a typical application workload on the system, run the AUTOGEN.COM
procedure again to tune the system properly. Run AUTOGEN as follows.
(In an OpenVMS Cluster, you must follow these steps to run AUTOGEN
on each cluster node.)
Run AUTOGEN in feedback mode, examine AGEN$PARAMS.REPORT,
and reboot the system. To run AUTOGEN in feedback mode, use the
$ @SYS$UPDATE:AUTOGEN SAVPARAMS SETPARAMS FEEDBACK
To view AGEN$PARAMS.REPORT on your screen, enter the following
$ TYPE SYS$SYSTEM:AGEN$PARAMS.REPORT
You can print this file or examine it using the EDIT/READ_ONLY
If the report includes a message similar to the following,
you might need to modify the size of the page, swap, or dump file:
%AUTOGEN-W-DSKSPC, The disk on which DKA0:[SYS0.SYSEXE]PAGEFILE.SYS
resides would be over 95% full if it were modified to hold 20000 blocks.
For more information about AGEN$PARAMS.REPORT, see the HP OpenVMS System Manager's Manual, Volume 2: Tuning, Monitoring, and Complex Systems.
Run AUTOGEN again in feedback mode two work days later
and examine AGEN$PARAMS.REPORT, and then reboot the system. (For
information about the importance of having a current AGEN$FEEDBACK.DAT
file, see “Ensuring You Have
a Recent FEEDBACK.DAT File”.)
HP recommends that you run AUTOGEN from the SAVPARAMS
phase through the TESTFILES phase weekly thereafter until the system
stabilizes (that is, until AUTOGEN finds nothing that needs to be
adjusted). Make sure you run AUTOGEN when your system is running
under a typical workload. Examine AGEN$PARAMS.REPORT to determine
the need for additional changes.
|IMPORTANT: If you start AUTOGEN without specifying the execution-mode
parameter (FEEDBACK, NOFEEDBACK, or CHECK_FEEDBACK), AUTOGEN uses
the feedback information in its calculations. However, if the feedback
information reflects system up time of less than 24 hours, or if
the feedback information is more than 30 days old, AUTOGEN includes
warnings in the AGEN$PARAMS.REPORT file to alert you to potential
problems with the feedback data. If you wrongly assume the feedback
is valid, the parameter settings might vary significantly from your expectations.|
If you specify FEEDBACK (or NOFEEDBACK), AUTOGEN uses (or
does not use) the feedback regardless of the data’s reliability.
AUTOGEN proceeds through the SETPARAMS phase (if you specified
SETPARAMS, SHUTDOWN, or REBOOT as the end phase) and sets system
parameters to the values it computed.
If you specify CHECK_FEEDBACK, AUTOGEN checks the validity
of the feedback data. If AUTOGEN determines the feedback is suspect,
then AUTOGEN ignores the feedback when computing parameter values.
It stops at the TESTFILES phase and issues a warning in the report
that parameters have not been changed. You must read the report
and decide whether the calculated values are acceptable. You can either
use them (by running the AUTOGEN SETPARAMS phase) or rerun AUTOGEN
with valid feedback data.
After the system has stabilized,
HP recommends that you run AUTOGEN at least monthly to save feedback
information for future use. Use the following command:
$ @SYS$UPDATE:AUTOGEN SAVPARAMS
If you do not maintain current feedback information for AUTOGEN,
you will not have the needed information the next time you upgrade
your system. As a result, you may have to reboot and rerun AUTOGEN
several times to make your upgraded system operational.
For more information about running AUTOGEN, see the HP OpenVMS System Manager's Manual, Volume 2: Tuning, Monitoring, and Complex Systems.