pmdaoverhead(1) — Linux manual page
PMDAOVERHEAD(1) General Commands Manual PMDAOVERHEAD(1)
NAME
pmdaoverhead - performance metrics domain agent (PMDA) exporting
resource consumption metrics for groups of processes
SYNOPSIS
$PCP_PMDAS_DIR/overhead/pmdaoverhead [-C] [-c config] [-d domain]
[-l logfile] [-R interval]
DESCRIPTION
pmdaoverhead is a configurable Performance Metrics Domain Agent
(PMDA) for exporting resource consumption for groups of related
processes.
The pmdaoverhead command line options are:
-C parse the configuration file(s) and exit after reporting any
errors.
-c configuration file(s), config may be either a file or a
directory; in the latter case all the files within config are
assumed to be configuration files for pmdaoverhead and they
will all be processed.
Each configuration file defines one or more ``groups'' of
processes of interest, using the syntax described in the
``CONFIGURATION'' section below.
By default all configuration files below the
$PCP_SYSCONF_DIR/overhead/conf.d/ directory are used.
-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.
-l Location of the log file. By default, a log file named
overhead.log is written in the current directory of pmcd(1)
when pmdaoverhead 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.
-R The PMDA uses a separate thread to periodically scan all
processes to determine which processes are deemed
``interesting'' in each group, and extracting resource
consumption for those processes. The interval (in seconds)
determines how often this scanning and resource calculation
is done, the default is 60 (seconds).
CONFIGURATION
Each configuration file defines one or more ``groups'' of
processes. The file format is simple and follows the following
rules.
1. Lines beginning with a hash ``#'' are treated as comments.
More generally, except for the pattern: clause described
below, all text between a hash and the end of line is treated
as a comment.
2. White space (spaces or tabs or newlines) are required to
separate lexical components. Spaces and tabs are otherwise
ignored. Other than terminating comments and the regex in a
pattern: clause, newlines are also ignored.
3. Each group is introduced by a group clause that has the form
group name { parameters }
where name is a unique name for the group across all groups
in the pmdaoverhead configuration files. As name becomes
embedded in the Performance Metrics Name Space (PMNS) if must
follow the rules for metric name components as described in
PMNS(5), namely beginning with an alphabetic character,
followed by zero or more characters drawn from the
alphabetics, numerics and the underscore ``_'' character.
4. The parameters must include one id: clause and one pattern:
clause.
5. An id: clause has the form
id: ident
where ident is a unique identifier number for the group
across all groups in the pmdaoverhead configuration files.
Valid values for ident are in the range 0 to 4094
(inclusive).
6. A pattern: clause has the form
pattern: regex
where regex is an extended regular expression notation in the
style of egrep(1). The regex starts at the first non-
whitespace character after pattern: and extends to the next
newline.
The processes that are considered to be members of the group
are those for which the command name, as reported by
$ pminfo -f proc.psinfo.cmd
is matched by regex plus all the descendents of those
processes. So for example the regex ^pmcd$ will match
pmcd(1) and all the PMDA processes launched by pmcd(1) and
any of their children, etc.
INSTALLATION
If you want access to the names, help text and values for the
overhead performance metrics, do the following as root:
# cd $PCP_PMDAS_DIR/overhead
# ./Install
If you want to undo the installation, do the following as root:
# cd $PCP_PMDAS_DIR/overhead
# ./Remove
pmdaoverhead is launched by pmcd and should never be executed
directly. The Install and Remove scripts notify pmcd when the
agent is installed or removed.
FILES
$PCP_PMCDCONF_PATH
command line options used to launch pmdaoverhead
$PCP_PMDAS_DIR/overhead/Install
installation script for the pmdaoverhead agent
$PCP_PMDAS_DIR/overhead/Remove
undo installation script for the pmdaoverhead agent
$PCP_LOG_DIR/pmcd/overhead.log
default log file for error messages and other information
from pmdaoverhead
$PCP_SYSCONF_DIR/overhead/conf.d
directory containing configuration files for the overhead
metrics
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).
SEE ALSO
PCPIntro(1), pmcd(1), pmdaproc(1), pcp.conf(5), pcp.env(5) and
PMNS(5).
COLOPHON
This page is part of the PCP (Performance Co-Pilot) project.
Information about the project can be found at
⟨http://www.pcp.io/⟩. If you have a bug report for this manual
page, send it to pcp@groups.io. This page was obtained from the
project's upstream Git repository
⟨https://github.com/performancecopilot/pcp.git⟩ on 2024-06-14.
(At that time, the date of the most recent commit that was found
in the repository was 2024-06-14.) If you discover any rendering
problems in this HTML version of the page, or you believe there
is a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
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