NAME¶
pmdaproc - process performance metrics domain agent (PMDA)
SYNOPSIS¶
$PCP_PMDAS_DIR/proc/pmdaproc [
-AL] [
-d domain] [
-l logfile] [
-r cgroup] [
-U
username]
DESCRIPTION¶
pmdaproc is a Performance Metrics Domain Agent (PMDA) which extracts
performance metrics describing the state of the individual processes running
on a Linux system.
The
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
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
PCPIntro(1) page.
A brief description of the
pmdaproc command line options follows:
- -A
- Disables use of the credentials provided by PMAPI client tools, and
simply runs everything under the "root" account.
- -L
- Changes the per-process instance domain used by most procproc
metrics to include threads as well.
- -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 proc.log is
written in the current directory of pmcd(1) when pmdaproc 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
- Restrict the set of processes exported in the per-process instance domain
to only those processes that are contained by the specified cgroup
resource container. This option provides an optional finer granularity to
the monitoring, and can also be used to reduce the resources consumed by
pmdaproc during requests for instances and values.
- -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.
INSTALLATION¶
The
proc PMDA is installed and available by default. If you want to undo
the installation, do the following as root:
# cd $PCP_PMDAS_DIR/proc
# ./Remove
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:
# cd $PCP_PMDAS_DIR/proc
# ./Install
pmdaproc 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 pmdaproc
- $PCP_PMDAS_DIR/proc/help
- default help text file for the proc metrics
- $PCP_PMDAS_DIR/proc/Install
- installation script for the pmdaproc agent
- $PCP_PMDAS_DIR/proc/Remove
- undo installation script for the pmdaproc agent
- $PCP_LOG_DIR/pmcd/proc.log
- default log file for error messages and other information from
pmdaproc
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),
seteuid(2),
setegid(2),
PMAPI(3),
pcp.conf(5) and
pcp.env(5).