Ubuntu Manpage: PCPIntro - introduction to the Performance Co-Pilot (PCP)

NAME

       PCPIntro - introduction to the Performance Co-Pilot (PCP)

INTRODUCTION

       The  Performance  Co-Pilot  (PCP)  is  a  toolkit  designed  for  monitoring  and  managing  system-level
       performance.  These services are  distributed  and  scalable  to  accommodate  the  most  complex  system
       configurations and performance problems.

       PCP supports many different platforms, including (but not limited to) Linux, MacOSX, Solaris and Windows.
       From a high-level PCP can be considered to contain two classes of software utility:

       PCP Collectors
               These are the parts of PCP that collect and extract performance data from various  sources,  e.g.
               the operating system kernel.

       PCP Monitors
               These are the parts of PCP that display data collected from hosts (or archives) that have the PCP
               Collector installed.  Many monitor tools are available as part of the  core  PCP  release,  while
               other (typically graphical) monitoring tools are available separately in the PCP GUI package.

       This manual entry describes the high-level features and options common to most PCP utilities available on
       all platforms.

OVERVIEW

The PCP architecture is distributed in the sense that any PCP tool may be executing remotely. On the
host (or hosts) being monitored, each domain of performance metrics, whether the kernel, a service layer,
a database management system, a web server, an application, etc. requires a Performance Metrics Domain
Agent (PMDA) which is responsible for collecting performance measurements from that domain. All PMDAs
are controlled by the Performance Metrics Collector Daemon (pmcd(1)) on the same host.

Client applications (the monitoring tools) connect to pmcd(1), which acts as a router for requests, by
forwarding requests to the appropriate PMDA and returning the responses to the clients. Clients may also
access performance data from a PCP archive (created using pmlogger(1)) for retrospective analysis.

Security philosophy
PCP redistributes a wealth of performance information within a host and across its networks. The
following security philosophy underlies the setting of several defaults that control how much information
is sent and received.

By default, the information exposed by PMCD about a host is approximately of the same level of
confidentiality as available to a completely unprivileged user on that host. So, performance data that
is available to be read completely freely on a machine may be made available by PMCD to the network.

However, the host running PMCD and its network is not assumed to run only friendly applications.
Therefore, write type operations, including from the local host, are not permitted by default.

These defaults may be overridden (expanded or reduced) in several ways, including by specifying network
ACLs in pmcd.conf, activating non-default PMDAs, or by using PMCD connections that pass user credentials.
For example, some PMDAs automatically provide greater information for particular credentialed users or
groups.

Applications
The following performance monitoring applications are primarily console based, typically run directly
from the command line, and are just a small subset of the tools available as part of the base PCP
package.

Each tool or command is documented completely in its own reference page.

pmstat Outputs an ASCII high-level summary of system performance.

pmie An inference engine that can evaluate predicate-action rules to perform alarms and automate system
management tasks.

pminfo Interrogate specific performance metrics and the metadata that describes them.

pmlogger
Generates PCP archives of performance metrics suitable for replay by most PCP tools.

pmval Simple periodic reporting for some or all instances of a performance metric, with optional VCR
time control.

If the PCP GUI package is installed then the following additional tools are available.

pmchart
Displays trends over time of arbitrarily selected performance metrics from one or more hosts.

pmtime Time control utility for coordinating the time between multiple tools (including pmchart and
pmval).

pmdumptext
Produce ASCII reports for arbitrary combinations of performance metrics.

COMMON COMMAND LINE ARGUMENTS

There is a set of common command line arguments that are used consistently by most PCP tools.

-a archive
Performance metric information is retrospectively retrieved from the Performance Co-Pilot (PCP)
archive, previously generated by pmlogger(1). The -a and -h options are mutually exclusive.

archive is either the base name common to all of the physical files created by an instance of
pmlogger(1), or any one of the physical files, e.g. myarchive (base name) or myarchive.meta (the
metadata file) or myarchive.index (the temporal index) or myarchive.0 (the first data volume of
archive) or myarchive.0.bz2 or myarchive.0.bz (the first data volume compressed with bzip2(1)) or
myarchive.0.gz or myarchive.0.Z or myarchive.0.z (the first data volume compressed with gzip(1)),
myarchive.1 or myarchive.3.bz2 or myarchive.42.gz etc.

-a archive[,archive,...]
An alternate form of -a for applications that are able to handle multiple archives.

-h hostname
Unless directed to another host by the -h option, or to an archive by the -a option, the source of
performance metrics will be the Performance Metrics Collector Daemon (PMCD) on the local host.
Refer to the PMCD HOST SPECIFICATION section later for further details on the many options
available when forming the hostname specification, as well as a detailed description of the
default local host connection. The -a and -h options are mutually exclusive.

-s samples
The argument samples defines the number of samples to be retrieved and reported. If samples is 0
or -s is not specified, the application will sample and report continuously (in real time mode) or
until the end of the PCP archive (in archive mode).

-z Change the reporting timezone to the local timezone at the host that is the source of the
performance metrics, as identified via either the -h or -a options.

-Z timezone
By default, applications report the time of day according to the local timezone on the system
where the application is executed. The -Z option changes the timezone to timezone in the format
of the environment variable TZ as described in environ(5).

INTERVAL SPECIFICATION AND ALIGNMENT

Most PCP tools operate with periodic sampling or reporting, and the -t and -A options may be used to
control the duration of the sample interval and the alignment of the sample times.

-t interval
Set the update or reporting interval.

The interval argument is specified as a sequence of one or more elements of the form
number[units]
where number is an integer or floating point constant (parsed using strtod(3)) and the optional
units is one of: seconds, second, secs, sec, s, minutes, minute, mins, min, m, hours, hour, h,
days, day and d. If the unit is empty, second is assumed.

In addition, the upper case (or mixed case) version of any of the above is also acceptable.

Spaces anywhere in the interval are ignored, so 4 days 6 hours 30 minutes, 4day6hour30min, 4d6h30m
and 4d6.5h are all equivalent.

Multiple specifications are additive, e.g. ``1hour 15mins 30secs'' is interpreted as 3600+900+30
seconds.

-A align
By default samples are not necessarily aligned on any natural unit of time. The -A option may be
used to force the initial sample to be aligned on the boundary of a natural time unit. For
example -A 1sec, -A 30min and -A 1hour specify alignment on whole seconds, half and whole hours
respectively.

The align argument follows the syntax for an interval argument described above for the -t option.

Note that alignment occurs by advancing the time as required, and that -A acts as a modifier to
advance both the start of the time window (see the next section) and the origin time (if the -O
option is specified).

TIME WINDOW SPECIFICATION

       Many PCP tools are designed to operate in some time window of interest, e.g. to define a termination time
       for real-time monitoring or to define a start and end time within a PCP archive log.

       In  the absence of the -O and -A options to specify an initial sample time origin and time alignment (see
       above), the PCP application will retrieve the first sample at the start of the time window.

       The following options may be used to specify a time window of interest.

       -S starttime
              By default the time window commences immediately in real-time mode, or coincides with time at  the
              start  of  the PCP archive log in archive mode.  The -S option may be used to specify a later time
              for the start of the time window.

              The starttime parameter may be given in one of three forms (interval is the same  as  for  the  -t
              option as described above, ctime is described below):

              interval
                     To  specify  an  offset from the current time (in real-time mode) or the beginning of a PCP
                     archive (in archive mode) simply specify the interval of time as the argument.  For example
                     -S  30min  will set the start of the time window to be exactly 30 minutes from now in real-
                     time mode, or exactly 30 minutes from the start of a PCP archive.

              -interval
                     To specify an offset from the end of a PCP archive log, prefix the interval argument with a
                     minus  sign.   In  this  case, the start of the time window precedes the time at the end of
                     archive by the given interval.  For example -S -1hour will set the start of the time window
                     to be exactly one hour before the time of the last sample in a PCP archive log.

              @ctime To  specify the calendar date and time (local time in the reporting timezone) for the start
                     of the time window, use the ctime(3) syntax preceded by an at sign.  For example -S '@  Mon
                     Mar 4 13:07:47 1996'

       -T endtime
              By default the end of the time window is unbounded (in real-time mode) or aligned with the time at
              the end of a PCP archive log (in archive mode).  The -T option may be used to specify  an  earlier
              time for the end of the time window.

              The  endtime  parameter  may  be  given  in one of three forms (interval is the same as for the -t
              option as described above, ctime is described below):

              interval
                     To specify an offset from the start of the time window simply use the interval of  time  as
                     the  argument.   For example -T 2h30m will set the end of the time window to be 2 hours and
                     30 minutes after the start of the time window.

              -interval
                     To specify an offset back from the time at the  end  of  a  PCP  archive  log,  prefix  the
                     interval  argument  with  a  minus  sign.  For example -T -90m will set the end of the time
                     window to be 90 minutes before the time of the last sample in a PCP archive log.

              @ctime To specify the calendar date and time (local time in the reporting timezone) for the end of
                     the time window, use the ctime(3) syntax preceded by an at sign.  For example -T '@ Mon Mar
                     4 13:07:47 1996'

       -O origin
              By default samples are fetched from the start of the time window (see description of -S option) to
              the end of the time window (see description of -T option).  The -O option allows the specification
              of an origin within the time window to be used as the initial sample time.   This  is  useful  for
              interactive use of a PCP tool with the pmtime(1) VCR replay facility.

              The  origin  argument  accepted  by  -O conforms to the same syntax and semantics as the starttime
              argument for the -T option.

              For example -O -0 specifies that the initial position should be at the end  of  the  time  window;
              this is most useful when wishing to replay ``backwards'' within the time window.

       The  ctime  argument  for  the  -O,  -S and -T options is based upon the calendar date and time format of
       ctime(3), but may be a fully specified time string like Mon Mar  4 13:07:47 1996 or a partially specified
       time like Mar 4 1996, Mar 4, Mar, 13:07:50 or 13:08.

       For any missing low order fields, the default value of 0 is assumed for hours, minutes and seconds, 1 for
       day of the month and Jan for months.  Hence, the following are equivalent: -S '@ Mar 1996' and -S '@  Mar
       1 00:00:00 1996'.

       If  any  high  order fields are missing, they are filled in by starting with the year, month and day from
       the current time (real-time mode) or the time at the beginning of the PCP archive log (archive mode)  and
       advancing  the  time  until it matches the fields that are specified.  So, for example if the time window
       starts by default at ``Mon Mar 4 13:07:47 1996'', then -S @13:10 corresponds to 13:10:00 on  Mon  Mar  4,
       1996, while -S @10:00 corresponds to 10:00:00 on Tue Mar 5, 1996 (note this is the following day).

       For greater precision than afforded by ctime(3), the seconds component may be a floating point number.

       Also the 12 hour clock (am/pm notation) is supported, so for example 13:07 and 1:07 pm are equivalent.

PERFORMANCE METRICS - NAMES AND IDENTIFIERS

The number of performance metric names supported by PCP on most platforms ranges from many hundreds to
several thousand. The PCP libraries and applications use an internal identification scheme that
unambiguously associates a single integer with each known performance metric. This integer is known as
the Performance Metric Identifier, or PMID. Although not a requirement, PMIDs tend to have global
consistency across all systems, so a particular performance metric usually has the same PMID.

For all users and most applications, direct use of the PMIDs would be inappropriate (e.g. this would
limit the range of accessible metrics, make the code hard to maintain, force the user interface to be
particularly baroque, etc.). Hence a Performance Metrics Name Space (PMNS) is used to provide external
names and a hierarchic classification for performance metrics. A PMNS is represented as a tree, with
each node having a label, a pointer to either a PMID (for leaf nodes) or a set of descendent nodes in the
PMNS (for non-leaf nodes).

A node label must begin with an alphabetic character, followed by zero or more characters drawn from the
alphabetics, the digits and character `_´ (underscore). For alphabetic characters in a node label, upper
and lower case are distinguished.

By convention, the name of a performance metric is constructed by concatenation of the node labels on a
path through the PMNS from the root node to a leaf node, with a ``.'' as a separator. The root node in
the PMNS is unlabeled, so all names begin with the label associated with one of the descendent nodes
below the root node of the PMNS, e.g. kernel.percpu.syscall. Typically (although this is not a
requirement) there would be at most one name for each PMID in a PMNS. For example kernel.all.cpu.idle
and disk.dev.read are the unique names for two distinct performance metrics, each with a unique PMID.

Groups of related PMIDs may be named by naming a non-leaf node in the PMNS tree, e.g. disk.

The default local PMNS used by pmcd is located at $PCP_VAR_DIR/pmns/root however the environment variable
PMNS_DEFAULT may be set to the full pathname of a different PMNS which will then be used as the default
local PMNS.

Most applications do not use the local PMNS directly, but rather import parts of the PMNS as required
from the same place that performance metrics are fetched, i.e. from pmcd(1) for live monitoring or from a
PCP archive for retrospective monitoring.

To explore the PMNS use pminfo(1), or if the PCP GUI package is installed the New Chart and Metric Search
windows within pmchart(1).

PERFORMANCE METRIC SPECIFICATIONS

       In configuration files and (to a lesser extent) command line options, metric specifications adhere to the
       following syntax rules.

       If the source of performance metrics is real-time from pmcd(1) then the accepted syntax is
                 host:metric[instance1,instance2,...]

       If the source of performance metrics is a PCP archive log then the accepted syntax is
                 archive/metric[instance1,instance2,...]

       The host:, archive/ and [instance1,instance2,...]  components are all optional.

       The , delimiter in the list of instance names may be replaced by white space.

       Special characters in instance names may be escaped by surrounding the name in double quotes or preceding
       the character with a backslash.

       White space is ignored everywhere except within a quoted instance name.

       An empty instance is silently ignored, and in particular  ``[]''  is  the  same  as  no  instance,  while
       ``[one,,,two]'' is parsed as specifying just the two instances ``one'' and ``two''.

       As  a  special  case,  if  the  host is the single character ``@'' then this refers to a PM_CONTEXT_LOCAL
       source, see pmNewContext(3).

SECURE PMCD CONNECTIONS

       Since PCP version 3.6.11, a monitor can explicitly request  a  secure  connection  to  a  collector  host
       running  pmcd(1)  or  pmproxy(1)  using  the  PM_CTXFLAG_SECURE  context flag.  If the PCP Collector host
       supports this feature - refer to the pmcd.feature.secure metric for confirmation  of  this  -  a  TLS/SSL
       (Transport  Layer  Security  or Secure Sockets Layer) connection can be established which uses public key
       cryptography and related techniques.  These features aim to prevent eavesdropping and data tampering from
       a  malicious  third party, as well as providing server-side authentication (confident identification of a
       server by a client) which can be used to guard against man-in-the-middle attacks.

       A secure pmcd connection requires use of certificate-based authentication.  The security features offered
       by  pmcd  and  pmproxy are implemented using the Network Security Services (NSS) APIs and utilities.  The
       NSS certutil tool can be used to create certificates suitable for establishing trust between PCP  monitor
       and collector hosts.

       A  complete description is beyond the scope of this document, refer to the PCP ENVIRONMENT, FILES and SEE
       ALSO sections for detailed information.  This includes links  to  tutorials  on  the  steps  involved  in
       setting up the available security features.

PMCD HOST SPECIFICATION

In the absence of an explicit host name specification, most tools will default to the local host in live
update mode. In PCP releases since 3.8.4 onward, this results in an efficient local protocol being
selected - typically a Unix domain socket. If this option is used (which can also be explicitly
requested via the unix: host specification described below), it is important to note that all connections
will be automatically authenticated. In other words, the credentials of the user invoking a client tool
will automatically be made available to pmcd(1) and all of its PMDAs, on the users behalf, such that
results can be customized to the privilege levels of individual users.

Names of remote hosts running the pmcd(1) daemon can of course also be provided to request a remote host
be used. The most basic form of pmcd host specification is a simple host name, possibly including the
domain name if necessary. However, this can be extended in a number of ways to further refine attributes
of the connection made to pmcd.

The pmcd port number and also optional pmproxy(1) hostname and its port number, can be given as part of
the host specification, since PCP version 3.0. These supersede (and override) the old-style PMCD_PORT,
PMPROXY_HOST and PMPROXY_PORT environment variables.

The following are valid hostname specifications that specify connections to pmcd on host nas1.servers.com
with/without a list of ports and with/without a pmproxy(1) connection through a firewall.

$ pcp -h nas1.servers.com:44321,4321@firewall.servers.com:44322
$ pcp -h nas1.servers.com:44321@firewall.servers.com:44322
$ pcp -h nas1.servers.com:44321@firewall.servers.com
$ pcp -h nas1.servers.com@firewall.servers.com
$ pcp -h nas1.servers.com:44321

In addition, security attributes and credentials can also be specified. These include username, an
optional password (can be given interactively and may depend on the authentication mechanism employed),
whether to use secure (encrypted) or native (naked) protocol, and so on. The previous examples all
default to native protocol, and use no authentication. This can be altered, as in the following
examples.

$ pcp -h pcps://nas1.servers.com:44321?username=tanya&method=gssapi
$ pcp -h pcps://nas2.servers.com@firewalls.r.us?method=plain
$ pcp -h pcp://nas3.servers.com
$ pcp -h unix:
$ pcp -h local:

The choice of authentication method, and other resulting parameters like username, optionally password,
etc, depends on the SASL2 configuration used by each (remote) pmcd. Tutorials are available specifying
various aspects of configuring the authentication module(s) used, these fine details are outside the
scope of this document.

The final local: example above is now the default for most tools. This connection is an automatically
authenticated local host connection on all platforms that support Unix domain sockets. No password is
required and authentication is automatic. This is also the most efficient (lowest overhead)
communication channel available.

The difference between unix: and local: is that the former is a strict Unix domain socket specification
(connection fails if it cannot connect that way), whereas the latter has a more forgiving fallback to
using localhost (i.e. a regular Inet socket connection is used when Unix domain socket connections are
unavailable).

ENVIRONMENT

In addition to the PCP run-time environment and configuration variables described in the PCP ENVIRONMENT
section below, the following environment variables apply to all installations.

PCP_CONSOLE
When set, this changes the default console from /dev/tty (on Unix) or CON: (on Windows) to be the
specified console. The special value of none can be used to indicate no console is available for
use. This is used in places where console-based tools need to interact with the user, and in
particular is used when authentication is being performed.

PCP_DERIVED_CONFIG
When set, this variable defines the path to a file that contains definitions of derived metrics as
per the syntax described in pmLoadDerivedConfig(3). Derived metrics may be used to extend the
available metrics with new (derived) metrics using simple arithmetic expressions.

If PCP_DERIVED_CONFIG is set, the derived metric definitions are processed automatically as each
new source of performance metrics is established (i.e. each time a pmNewContext(3) is called) or
when requests are made against the PMNS.

PCP_SECURE_SOCKETS
When set, this variable forces any monitor tool connections to be established using the
certificate-based secure sockets feature. If the connections cannot be established securely, they
will fail.

PCP_SECURE_DB_METHOD
With secure socket connections, the certificate and key database is stored using the sql: method
by default. Use PCP_SECURE_DB_METHOD to override the default, most usually setting the value to
the empty string (for the older database methods).

PCP_STDERR
Many PCP tools support the environment variable PCP_STDERR, which can be used to control where
error messages are sent. When unset, the default behavior is that ``usage'' messages and option
parsing errors are reported on standard error, other messages after initial startup are sent to
the default destination for the tool, i.e. standard error for ASCII tools, or a dialog for GUI
tools.

If PCP_STDERR is set to the literal value DISPLAY then all messages will be displayed in a dialog.
This is used for any tools launched from the a Desktop environment.

If PCP_STDERR is set to any other value, the value is assumed to be a filename, and all messages
will be written there.

PMCD_CONNECT_TIMEOUT
When attempting to connect to a remote pmcd(1) on a machine that is booting, the connection
attempt could potentially block for a long time until the remote machine finishes its
initialization. Most PCP applications and some of the PCP library routines will abort and return
an error if the connection has not been established after some specified interval has elapsed.
The default interval is 5 seconds. This may be modified by setting PMCD_CONNECT_TIMEOUT in the
environment to a real number of seconds for the desired timeout. This is most useful in cases
where the remote host is at the end of a slow network, requiring longer latencies to establish the
connection correctly.

PMCD_RECONNECT_TIMEOUT
When a monitor or client application loses a connection to a pmcd(1), the connection may be re-
established by calling a service routine in the PCP library. However, attempts to reconnect are
controlled by a back-off strategy to avoid flooding the network with reconnection requests. By
default, the back-off delays are 5, 10, 20, 40 and 80 seconds for consecutive reconnection
requests from a client (the last delay will be repeated for any further attempts after the fifth).
Setting the environment variable PMCD_RECONNECT_TIMEOUT to a comma separated list of positive
integers will re-define the back-off delays, e.g. setting PMCD_RECONNECT_TIMEOUT to ``1,2'' will
back-off for 1 second, then attempt another connection request every 2 seconds thereafter.

PMCD_REQUEST_TIMEOUT
For monitor or client applications connected to pmcd(1), there is a possibility of the application
"hanging" on a request for performance metrics or metadata or help text. These delays may become
severe if the system running pmcd crashes, or the network connection is lost. By setting the
environment variable PMCD_REQUEST_TIMEOUT to a number of seconds, requests to pmcd will timeout
after this number of seconds. The default behavior is to be willing to wait 10 seconds for a
response from every pmcd for all applications.

PMCD_WAIT_TIMEOUT
When pmcd(1) is started from $PCP_RC_DIR/pcp then the primary instance of pmlogger(1) will be
started if the configuration flag pmlogger is chkconfig'ed on and pmcd is running and accepting
connections.

The check on pmcd's readiness will wait up to PMCD_WAIT_TIMEOUT seconds. If pmcd has a long
startup time (such as on a very large system), then PMCD_WAIT_TIMEOUT can be set to provide a
maximum wait longer than the default 60 seconds.

PMNS_DEFAULT
If set, then interpreted as the full pathname to be used as the default local PMNS for
pmLoadNameSpace(3). Otherwise, the default local PMNS is located at $PCP_VAR_DIR/pcp/pmns/root
for base PCP installations.

PCP_COUNTER_WRAP
Many of the performance metrics exported from PCP agents have the semantics of counter meaning
they are expected to be monotonically increasing. Under some circumstances, one value of these
metrics may smaller than the previously fetched value. This can happen when a counter of finite
precision overflows, or when the PCP agent has been reset or restarted, or when the PCP agent is
exporting values from some underlying instrumentation that is subject to some asynchronous
discontinuity.

The environment variable PCP_COUNTER_WRAP may be set to indicate that all such cases of a
decreasing ``counter'' should be treated as a counter overflow, and hence the values are assumed
to have wrapped once in the interval between consecutive samples. This ``wrapping'' behavior was
the default in earlier PCP versions, but by default has been disabled in PCP release from version
1.3 on.

PMDA_PATH
The PMDA_PATH environment variable may be used to modify the search path used by pmcd(1) and
pmNewContext(3) (for PM_CONTEXT_LOCAL contexts) when searching for a daemon or DSO PMDA. The
syntax follows that for PATH in sh(1), i.e. a colon separated list of directories, and the default
search path is ``/var/pcp/lib:/usr/pcp/lib'', (or ``/var/lib/pcp/lib'' on Linux, depending on the
value of the $PCP_VAR_DIR environment variable).

PMCD_PORT
The TPC/IP port(s) used by pmcd(1) to create the socket for incoming connections and requests, was
historically 4321 and more recently the officially registered port 44321; in the current release,
both port numbers are used by default as a transitional arrangement. This may be over-ridden by
setting PMCD_PORT to a different port number, or a comma-separated list of port numbers. If a
non-default port is used when pmcd is started, then every monitoring application connecting to
that pmcd must also have PMCD_PORT set in their environment before attempting a connection.

The following environment variables are relevant to installations in which pmlogger(1), the PCP archive
logger, is used.

PMLOGGER_PORT
The environment variable PMLOGGER_PORT may be used to change the base TCP/IP port number used by
pmlogger(1) to create the socket to which pmlc(1) instances will try and connect. The default
base port number is 4330. When used, PMLOGGER_PORT should be set in the environment before
pmlogger is executed.

PMLOGGER_REQUEST_TIMEOUT
When pmlc(1) connects to pmlogger(1), there is a remote possibility of pmlc "hanging" on a request
for information as a consequence of a failure of the network or pmlogger. By setting the
environment variable PMLOGGER_REQUEST_TIMEOUT to a number of seconds, requests to pmlogger will
timeout after this number of seconds. The default behavior is to be willing to wait forever for a
response from each request to a pmlogger. When used, PMLOGGER_REQUEST_TIMEOUT should be set in
the environment before pmlc is executed.

If you have the PCP product installed, then the following environment variables are relevant to the
Performance Metrics Domain Agents (PMDAs).

PMDA_LOCAL_PROC
Use this variable has been deprecated and it is now ignored. If the ``proc'' PMDA is configured
as a DSO for use with pmcd(1) on the local host then all of the ``proc'' metrics will be available
to applications using a PM_CONTEXT_LOCAL context.

The previous behaviour was that if this variable was set, then a context established with the type
of PM_CONTEXT_LOCAL will have access to the ``proc'' PMDA to retrieve performance metrics about
individual processes.

PMDA_LOCAL_SAMPLE
Use this variable has been deprecated and it is now ignored. If the ``sample'' PMDA is configured
as a DSO for use with pmcd(1) on the local host then all of the ``sample'' metrics will be
available to applications using a PM_CONTEXT_LOCAL context.

The previous behaviour was that if this variable was set, then a context established with the type
of PM_CONTEXT_LOCAL will have access to the ``sample'' PMDA if this optional PMDA has been
installed locally.

PMIECONF_PATH
If set, pmieconf(1) will form its pmieconf(5) specification (set of parameterized pmie(1) rules)
using all valid pmieconf files found below each subdirectory in this colon-separated list of
subdirectories. If not set, the default is $PCP_VAR_DIR/config/pmieconf.

FILES

/etc/pcp.conf
Configuration file for the PCP runtime environment, see pcp.conf(5).
/etc/pki/nssdb
Optionally contains a Network Security Services database with a "PCP Collector" certificate
providing trusted identification for the collector host.
$HOME/.pcp
User-specific directories containing configuration files for customisation of the various
monitor tools, such as pmchart(1).
$HOME/.pki/nssdb
A shared Network Security Services (NSS) database directory containing per-user certificates
identifying known valid remote pmcd collector hosts. The NSS certutil tool is one of several
that can be used to maintain this database.
$PCP_RC_DIR/pcp
Script for starting and stopping pmcd(1).
$PCP_PMCDCONF_PATH
Control file for pmcd(1).
$PCP_PMCDOPTIONS_PATH
Command line options passed to pmcd(1) when it is started from $PCP_RC_DIR/pcp. All the
command line option lines should start with a hyphen as the first character. This file can
also contain environment variable settings of the form "VARIABLE=value".
$PCP_BINADM_DIR
Location of PCP utilities for collecting and maintaining PCP archives, PMDA help text, PMNS
files etc.
$PCP_PMDAS_DIR
Parent directory of the installation directory for Dynamic Shared Object (DSO) PMDAs.
$PCP_RUN_DIR/pmcd.pid
If pmcd is running, this file contains an ascii decimal representation of its process ID.
$PCP_LOG_DIR/pmcd
Default location of log files for pmcd(1), current directory for running PMDAs. Archives
generated by pmlogger(1) are generally below $PCP_LOG_DIR/pmlogger.
$PCP_LOG_DIR/pmcd/pmcd.log
Diagnostic and status log for the current running pmcd(1) process. The first place to look
when there are problems associated with pmcd.
$PCP_LOG_DIR/pmcd/pmcd.log.prev
Diagnostic and status log for the previous pmcd(1) instance.
$PCP_LOG_DIR/NOTICES
Log of pmcd(1) and PMDA starts, stops, additions and removals.
$PCP_VAR_DIR/config
Contains directories of configuration files for several PCP tools.
$PCP_SYSCONF_DIR/pmcd/rc.local
Local script for controlling PCP boot, shutdown and restart actions.
$PCP_VAR_DIR/pmns
Directory containing the set of PMNS files for all installed PMDAs.
$PCP_VAR_DIR/pmns/root
The ASCII pmns(5) exported by pmcd(1) by default. This PMNS is be the super set of all other
PMNS files installed in $PCP_VAR_DIR/pmns.
In addition, if the PCP product is installed the following files and directories are relevant.
$PCP_LOG_DIR/NOTICES
In addition to the pmcd(1) and PMDA activity, may be used to log alarms and notices from pmie(1)
via pmpost(1).
$PCP_PMLOGGERCONTROL_PATH
Control file for pmlogger(1) instances launched from $PCP_RC_DIR/pcp and/or managed by
pmlogger_check(1) and pmlogger_daily(1) as part of a production PCP archive collection setup.

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).