Ubuntu Manpage: pmdasystemd - systemd performance metrics domain agent (PMDA)

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  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 pmcd(1)                      │
       ├────────┼──────────────────────────────────────────────────────────────────────────────────────────────┤
       │ appl2  │ trace select(2) calls                                                                        │
       └────────┴──────────────────────────────────────────────────────────────────────────────────────────────┘