Performance Co-Pilot overhead PMDA for Monitoring Groups of Processes
=====================================================================

This PMDA is designed to be configurable to monitor ...
TODO

The sample configuration file includes examples:

    + TODO

Metrics
=======

Once the PMDA has been installed, the following command will list all
the available metrics and their explanatory "help" text:

	$ pminfo -fT overhead

Installation of the overhead PMDA
=================================

 +  # cd $PCP_PMDAS_DIR/overhead

 +  Check that there is no clash with the Performance Metrics Domain
    number defined in ./domain.h and the other PMDAs currently in use
    (see $PCP_PMCDCONF_PATH).  If there is, edit ./domain.h and choose
    another domain number.

 +  Then run the Install script (as root)

	# ./Install

    Answer the questions, TODO
    See $PCP_PMDAS_DIR/overhead/sample.conf
    for examples of group specifications.

De-installation
===============

 +  Simply use

	# cd $PCP_PMDAS_DIR/overhead
	# ./Remove

Changing the settings
=====================

The refresh cycle time can be dynamically modified using pmstore(1)
for the metric overhead.control.refresh.

To make permanent changes, re-run the Install script.

Troubleshooting
===============

 +  After installing or restarting the agent, the PMCD log file
    ($PCP_LOG_DIR/pmcd/pmcd.log) and the PMDA log file
    ($PCP_LOG_DIR/pmcd/overhead.log) should be checked for any warnings
    or errors.

 +  If the Install script reports some warnings when checking the
    metrics, the problem should be listed in one of the log files.

 +  Additional information can be logged if there appears to be
    problems.  The PCP application debug flags will cause the PMDA to
    report additional information in $PCP_LOG_DIR/pmcd/overhead.log.
    Set debug flags by editing /etc/pcp/pmcd/pmcd.conf and adding
    -Dflag[,...] (see pmdbg -l for the available flags)