Section: User Commands (1)
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pmdatxmon - txmon performance metrics domain agent (PMDA)


$PCP_PMDAS_DIR/txmon/pmdatxmon [ -d domain ] [ -l logfile ] [ -U username ] tx_type ...
$PCP_PMDAS_DIR/txmon/txrecord [ -l ]
$PCP_PMDAS_DIR/txmon/txrecord tx_type servtime [ tx_type servtime ... ]


pmdatxmon is an example Performance Metrics Domain Agent (PMDA) which exports a small number of performance metrics from a simulated transaction monitor.

The txmon PMDA is shipped as both binary and source code and is designed to be an aid for PMDA developers; the txmon PMDA demonstrates how performance data can be exported from an application (in this case txrecord ) to the PCP infrastructure via a shared memory segment. As a matter of convenience, pmdatxmon creates (and destroys on exit) the shared memory segment.

The tx_type arguments are arbitrary unique tags used to identify different transaction types.

The txrecord application simulates the processing of one or more transactions identified by tx_type and with an observed service time of servtime .

With the -l option, txrecord displays the current summary of the transaction activity from the shared memory segment.

genload is a shell and awk (1) script that acts as a front-end to txrecord to generate a constant load of simulated transaction activity.

A brief description of the pmdatxmon command line options follows:

It is absolutely crucial that the performance metrics domain number specified here is unique and consistent. That is, domain should be different for every PMDA on the one host, and the same domain number should be used for the same PMDA on all hosts.
Location of the log file. By default, a log file named txmon.log is written in the current directory of pmcd (1) when pmdatxmon is started, i.e. $PCP_LOG_DIR/pmcd . If the log file cannot be created or is not writable, output is written to the standard error instead.
User account under which to run the agent. The default is the unprivileged "pcp" account in current versions of PCP, but in older versions the superuser account ("root") was used by default.


If you want access to the names, help text and values for the txmon performance metrics, do the following as root:

              # cd $PCP_PMDAS_DIR/txmon
              # ./Install

You will be prompted for the tx_type tags.

If you want to undo the installation, do the following as root:

              # cd $PCP_PMDAS_DIR/txmon
              # ./Remove

pmdatxmon is launched by pmcd (1) and should never be executed directly. The Install and Remove scripts notify pmcd (1) when the agent is installed or removed.


command line options used to launch pmdatxmon
default help text file for the txmon metrics
installation script for the pmdatxmon agent
undo installation script for the pmdatxmon agent
default log file for error messages and other information from pmdatxmon


Environment variables with the prefix PCP_ are used to parameterize the file and directory names used by PCP. On each installation, the file /etc/pcp.conf contains the local values for these variables. The $PCP_CONF variable may be used to specify an alternative configuration file, as described in pcp.conf (5).


PCPIntro (1), pmcd (1), pmdasample (1), pmdatrivial (1), txmonvis (1) and PMDA (3).