PMDASYSTEMD(1)

NAME
pmdasystemd - systemd performance metrics domain agent (PMDA)

SYNOPSIS
$PCP_PMDAS_DIR/systemd/pmdasystemd [-f] [-D debug] [-d domain] [-l logfile] [-m memory] [-s interval] [-U username]

DESCRIPTION
pmdasystemd is a systemd log file monitoring Performance Metrics Domain Agent (PMDA). It can be seen as analogous to the -f option to journalctl(1) and converts each new log line into a performance event, suitable for consumption by PMAPI(3) client tools like pmevent(1).

The systemd PMDA exports both event-style metrics reflecting timestamped event records for messages logged to the system logs, as well as the more orthodox sample-style metrics such as message counts and throughput size values.

A brief description of the pmdasystemd 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.

-f  Disables per-uid/gid record filtering. By default the user and group credentials will be used to filter log records returned to the client tool, preventing information exposure to arbitrary users. This option disables that, so use only with extreme caution.

-l  Location of the log file. By default, a log file named systemd.log is written in the current directory of pmcd(1) when pmdasystemd 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.

-m  Limit the physical memory used by the PMDA to buffer event records to maxsize bytes. As log events arrive at the PMDA, they must be buffered until individual client tools request the next batch since their previous batch of events. The default maximum is 2 megabytes.

-s  Sets the polling interval for detecting newly arrived log lines. Mirrors the same option from the tail(1) command.

-U  User account under which to run the agent. The default is the "adm" user account.

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

# cd $PCP_PMDAS_DIR/systemd
# ./Install

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

# cd $PCP_PMDAS_DIR/systemd
# ./Remove

pmdasystemd 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 pmdasystemd
$PCP_PMDAS_DIR/systemd/help
    default help text file for the systemd metrics
$PCP_PMDAS_DIR/systemd/Install
    installation script for the pmdasystemd agent
$PCP_PMDAS_DIR/systemd/Remove
    undo installation script for the pmdasystemd agent
$PCP_LOG_DIR/pmcd/systemd.log
    default log file for error messages and other information from pmdasystemd

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).

DEBUGGING OPTIONS
The -D or --debug option enables the output of additional diagnostics on stderr to help triage problems, although the information is sometimes cryptic and primarily intended to provide guidance for developers rather than for end-users. debug is a comma separated list of debugging options; use pmdbg(1) with the -l option to obtain a list of the available debugging options and their meaning.

Debugging options specific to pmdasystemd are as follows:
Option | Description
appl0 | filtering of journal records, access control, interactions with
appl2 | trace select(2) calls

SEE ALSO
PCPIntro(1), pmcd(1), pmevent(1), journalctl(1), tail(1), PMAPI(3), pcp.conf(5) and pcp.env(5).