'\"macro stdmacro
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.TH PMDAPROC 1 "PCP" "Performance Co-Pilot"
.SH NAME
\f3pmdaproc\f1 \- process performance metrics domain agent (PMDA)
.SH SYNOPSIS
\f3$PCP_PMDAS_DIR/proc/pmdaproc\f1
[\f3\-AL\f1]
[\f3\-d\f1 \f2domain\f1]
[\f3\-l\f1 \f2logfile\f1]
[\f3\-r\f1 \f2cgroup\f1]
[\f3\-U\f1 \f2username\f1]
.SH DESCRIPTION
.B pmdaproc
is a Performance Metrics Domain Agent (PMDA) which extracts
performance metrics describing the state of the individual
processes running on a Linux system.
.PP
The
.B proc
PMDA exports metrics that measure the memory, processor and
other resource use of each process, as well as summary information
collated across all of the running processes.
The PMDA uses credentials passed from the
.BR PMAPI (3)
monitoring tool identifying the user requesting the information,
to ensure that only values the user is allowed to access are
returned by the PMDA.
This involves the PMDA temporarily changing its effective user and
group identifiers for the duration of requests for instances and
values.
In other words, system calls to extract information are performed
as the user originating the request and not as a privileged user.
The mechanisms available for transfer of user credentials are
described further in the
.BR PCPIntro (1)
page.
.PP
A brief description of the
.B pmdaproc
command line options follows:
.TP 5
.B \-A
Disables use of the credentials provided by
.B PMAPI
client tools,
and simply runs everything under the "root" account.
.TP
.B \-L
Changes the per-process instance domain used by most
.B procproc
metrics to include threads as well.
.TP
.B \-d
It is absolutely crucial that the performance metrics
.I domain
number specified here is unique and consistent.
That is,
.I domain
should be different for every PMDA on the one host, and the same
.I domain
number should be used for the same PMDA on all hosts.
.TP
.B \-l
Location of the log file.  By default, a log file named
.I proc.log
is written in the current directory of
.BR pmcd (1)
when
.B pmdaproc
is started, i.e.
.BR $PCP_LOG_DIR/pmcd .
If the log file cannot
be created or is not writable, output is written to the standard error instead.
.TP
.B \-r
Restrict the set of processes exported in the per-process instance domain
to only those processes that are contained by the specified
.IR cgroup
resource container.
This option provides an optional finer granularity to the monitoring, and
can also be used to reduce the resources consumed by
.I pmdaproc
during requests for instances and values.
.TP
.B \-U
User account under which to run the agent.
The default is the privileged "root" account, with
seteuid (2)
and
setegid (2)
switching for accessing most information.
.SH INSTALLATION
The
.B proc
PMDA is installed and available by default.
If you want to undo the installation, do the following as root:
.PP
.ft CW
.nf
.in +0.5i
# cd $PCP_PMDAS_DIR/proc
# ./Remove
.in
.fi
.ft 1
.PP
If you want to establish access to the names, help text and values for the proc
performance metrics once more, after removal, do the following as root:
.PP
.ft CW
.nf
.in +0.5i
# cd $PCP_PMDAS_DIR/proc
# ./Install
.in
.fi
.ft 1
.PP
.B pmdaproc
is launched by
.BR pmcd (1)
and should never be executed directly.
The Install and Remove scripts notify
.BR pmcd (1)
when the agent is installed or removed.
.SH FILES
.PD 0
.TP 10
.B $PCP_PMCDCONF_PATH
command line options used to launch
.B pmdaproc
.TP 10
.B $PCP_PMDAS_DIR/proc/help
default help text file for the proc metrics
.TP 10
.B $PCP_PMDAS_DIR/proc/Install
installation script for the
.B pmdaproc
agent
.TP 10
.B $PCP_PMDAS_DIR/proc/Remove
undo installation script for the 
.B pmdaproc
agent
.TP 10
.B $PCP_LOG_DIR/pmcd/proc.log
default log file for error messages and other information from
.B pmdaproc
.PD
.SH "PCP ENVIRONMENT"
Environment variables with the prefix
.B PCP_
are used to parameterize the file and directory names
used by PCP.
On each installation, the file
.I /etc/pcp.conf
contains the local values for these variables.
The
.B $PCP_CONF
variable may be used to specify an alternative
configuration file,
as described in
.BR pcp.conf (5).
.SH SEE ALSO
.BR PCPIntro (1),
.BR pmcd (1),
.BR seteuid (2),
.BR setegid (2),
.BR PMAPI (3),
.BR pcp.conf (5)
and
.BR pcp.env (5).