NAME

pmdasimple - simple performance metrics domain agent (PMDA)

SYNOPSIS

$PCP_PMDAS_DIR/simple/pmdasimple [-d domain] [-i port] [-l logfile] [-p] [-u socket] [-U username]

DESCRIPTION

pmdasimple is a simple Performance Metrics Domain Agent (PMDA) which exports a small number of synthetic performance metrics.

The simple PMDA is shipped as source code and is designed to be an aid for PMDA developers. In terms of code size and features, it is more complex than the trivial PMDA, about the same as the txmon PMDA and less complex than the sample PMDA. The source for the simple PMDA is a good template from which production, customized PMDAs can be developed.

A brief description of the pmdasimple command line options follows:

-d: 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.
-i: Expect PMCD to connect to pmdasimple on the specified TCP/IP port. port may be a port number or port name.
-l: Location of the log file. By default, a log file named simple.log is written in the current directory of pmcd(1) when pmdasimple 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.
-p: Expect PMCD to create a pipe and the connection to pmdasimple is via standard input and standard output. This is the default connection mode.
-u: Expect PMCD to connect to pmdasimple on the Unix domain socket named socket.
-U: 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.

At most one of the options -i, -p and -u may be specified.

INSTALLATION

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



# cd $PCP_PMDAS_DIR/simple
# ./Install

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



# cd $PCP_PMDAS_DIR/simple
# ./Remove

pmdasimple 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.

FILES

$PCP_PMCDCONF_PATH

command line options used to launch pmdasimple

$PCP_PMDAS_DIR/simple/help

default help text file for the simple metrics

$PCP_PMDAS_DIR/simple/Install

installation script for the pmdasimple agent

$PCP_PMDAS_DIR/simple/Remove

undo installation script for the pmdasimple agent

$PCP_PMDAS_DIR/simple/simple.conf

configuration file for the dynamic instance domain that underlies the simple.now performance metric. For a description, refer to the help text file, or run the command

$ pminfo -T simple.now

$PCP_PMDAS_DIR/simple/*.pmda_simple.so

The DSO version of the PMDA. The same source is used to create both the DSO and the daemon versions of the simple PMDA, and one or the other may be installed as part of the dialog in the Install script.

$PCP_LOG_DIR/pmcd/simple.log

default log file for error messages and other information from pmdasimple

PCP ENVIRONMENT

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).