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HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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NAME | SYNOPSIS | DESCRIPTION | OPTIONS | CAVEATS | PCP ENVIRONMENT | SEE ALSO | COLOPHON |
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PMVAL(1) General Commands Manual PMVAL(1)
pmval, pmevent - arbitrary performance metrics value dumper
pmval [-dgLrvVXz?] [-a archive] [-A align] [--container=name]
[--derived=file] [-f N] [-h host] [-i instances] [-K spec] [-n
pmnsfile] [-O offset] [-p port] [-s samples] [-S starttime] [-t
interval] [-T endtime] [-U archive] [-w width] [-x pattern] [-Z
timezone] metricname
pmevent ...
pmval prints current or archived values for the nominated
performance metric. The metric of interest is named in the
metricname argument, subject to instance qualification with the
-i flag as described below.
Unless directed to another host by the -h option, or to a set of
archives by the -a or -U options, pmval will contact the
Performance Metrics Collector Daemon (PMCD) on the local host to
obtain the required information.
The metricname argument may also be given in the metric
specification syntax, as described in PCPIntro(1), where the
source, metric and instance may all be included in the
metricname, e.g. thathost:kernel.all.load["1 minute"]. When this
format is used, none of the -h or -a or -U options may be
specified.
When using the metric specification syntax, the ``hostname'' @ is
treated specially and causes pmval to use a local context to
collect metrics from PMDAs on the local host without PMCD. Only
some metrics are available in this mode.
When processing a set of archives, pmval may relinquish its own
timing control, and operate under the control of a a pmtime(1)
process that uses a GUI dialog to provide timing control. In
this case, either the -g option should be used to start pmval as
the sole client of a new pmtime(1) instance, or -p should be used
to attach pmval to an existing pmtime(1) instance via the IPC
channel identified by the port argument.
The -S, -T, -O and -A options may be used to define a time window
to restrict the samples retrieved, set an initial origin within
the time window, or specify a ``natural'' alignment of the sample
times; refer to PCPIntro(1) for a complete description of these
options.
The output from pmval is directed to standard output. The
following symbols may occasionally appear, in place of a metric
value, in pmval output: A question mark symbol (?) indicates
that a value is no longer available for that metric instance. An
exclamation mark (!) indicates that a 64-bit counter wrapped
during the sample.
pmevent is an alias for pmval.
The available command line options are:
-a archive, --archive=archive
Performance metric values are retrieved from the set of
Performance Co-Pilot (PCP) archive files identified by the
archive argument, which is a comma-separated list of names,
each of which may be the base name of an archive or the name
of a directory containing one or more archives. See also
-U.
-A align, --align=align
Force the initial sample to be aligned on the boundary of a
natural time unit align. Refer to PCPIntro(1) for a
complete description of the syntax for align.
--container=container
Specify an individual container to be queried.
-d, --delay
When replaying from an archive, this option requests that
the prevailing real-time delay be applied between samples
(see -t) to effect a pause, rather than the default
behaviour of replaying at full speed.
--derived=file
Load derived metric definitions from file.
-f precision, --precision=precision
Numbers are reported in ``fixed point'' notation, rather
than the default scientific notation, using precision digits
for precision. Each number will be up to the column width
determined by the default heuristics, else the -w option if
specified, and include precision digits after the decimal
point. So, the options -f 3 -w 8 would produce numbers of
the form 9999.999. A value of zero for precision omits the
decimal point and any fractional digits.
-g, --guimode
Start pmval as the sole client of a new pmtime(1) server
process for replay of archived performance data using the
pmtime(1) graphical user interface.
-h host, --host=host
Fetch performance metrics from pmcd(1) on host, rather than
from the default localhost.
-i instances, --instances=instances
Specify a list of one or more names of instances for the
nominated performance metric - just these instances will be
retrieved and reported (the default is to report all
instances). The list must be a single argument, with
elements of the list separated by commas and/or white space.
The instance name may be quoted with single (') or double
(") quotes for those cases where the instance name contains
white space or commas.
Multiple -i options are allowed as an alternative way of
specifying more than one instance of interest.
As an example, the following are all equivalent:
$ pmval -i "'1 minute','5 minute'" kernel.all.load
$ pmval -i '"1 minute","5 minute"' kernel.all.load
$ pmval -i "'1 minute' '5 minute'" kernel.all.load
$ pmval -i "'1 minute'" -i "'5 minute'" kernel.all.load
$ pmval 'localhost:kernel.all.load["1 minute","5 minute"]'
-K spec, --spec-local=spec
When fetching metrics from a local context (see -L), the -K
option may be used to control the DSO PMDAs that should be
made accessible. The spec argument conforms to the syntax
described in pmSpecLocalPMDA(3). More than one -K option
may be used.
-L, --local-PMDA
Use a local context to collect metrics from DSO PMDAs on the
local host without PMCD. See also -K.
-n pmnsfile, --namespace=pmnsfile
Load an alternative Performance Metrics Name Space (PMNS(5))
from the file pmnsfile.
-O origin, --origin=origin
When reporting archived metrics, start reporting at origin
within the time window (see -S and -T). Refer to
PCPIntro(1) for a complete description of the syntax for
origin.
-p port, --guiport=port
Attach pmval to an existing pmtime(1) time control process
instance via the IPC channel identified by the port
argument. This option is normally only used by other tools,
e.g. pmchart(1), when they launch pmval with synchronized
time control.
-r, --raw
Print raw values for cumulative counter metrics. Normally
cumulative counter metrics are converted to rates. For
example, disk transfers are reported as number of disk
transfers per second during the preceding sample interval,
rather than the raw value of number of disk transfers since
the machine was booted. If you specify this option, the raw
metric values are printed.
-s samples, --samples=samples
The samples argument defines the number of samples to be
retrieved and reported. If samples is 0 or -s is not
specified, pmval will sample and report continuously (in
real time mode) or until the end of the set of PCP archives
(in archive mode).
-S starttime, --start=starttime
When reporting archived metrics, the report will be
restricted to those records logged at or after starttime.
Refer to PCPIntro(1) for a complete description of the
syntax for starttime.
-t interval, --interval=interval
Set the reporting interval to something other than the
default 1 second. The interval argument follows the syntax
described in PCPIntro(1), and in the simplest form may be an
unsigned integer (the implied units in this case are
seconds).
-T endtime, --finish=endtime
When reporting archived metrics, the report will be
restricted to those records logged before or at endtime.
Refer to PCPIntro(1) for a complete description of the
syntax for endtime.
-U archive, --nointerp=archive
Performance metric values are retrieved from the Performance
Co-Pilot (PCP) archive. The argument is a comma-separated
list of names, each of which may be the base name of an
archive or the name of a directory containing one or more
archives. However, unlike -a every recorded value in the
archive for the selected metric and instances is reported
(so no interpolation mode, and the sample interval (-t
option) is ignored. See also -a.
At most one of the options -a and -U may be specified.
-v, --verbose
Enable verbose mode.
-V, --version
Display version number and exit.
-w width, --width=width
Set the width of each column of output to be width columns.
If not specified columns are wide enough to accommodate the
largest value of the type being printed.
-x pattern, --filter=pattern
The given pattern is sent to the performance metric domain
agent for the requested metricname before any values are
requested. This serves two purposes. Firstly, it provides
a mechanism for server-side event filtering that is
customisable for individual event streams. In addition,
some performance metrics domain agents also use the PMCD
store mechanism to provide a basic security model (e.g. for
sensitive log files, only a client host with pmStore(3)
access would be able to access the event stream).
As pattern may be processed by regcomp(3) it should be a
non-empty string. Use . (dot) for a “match all” pattern.
-X, --timestamp
When replaying from an archive, this option requests that
the timestamp be reported with additional date information
and increased precision (microseconds with a single -X,
nanoseconds with an additional -X), for example
Sat May 22 20:32:20.971633 2021 instead of the default
format, for example 20:32:20.971.
-z, --hostzone
Use the local timezone of the host that is the source of the
performance metrics, as identified by either the -h or the
-a or the -U options. The default is to use the timezone of
the local host.
-Z timezone, --timezone=timezone
Use timezone for the date and time. Timezone is in the
format of the environment variable TZ as described in
environ(7).
-?, --help
Display usage message and exit.
By default, pmval attempts to display non-integer numeric values
in a way that does not distort the inherent precision (rarely
more than 4 significant digits), and tries to maintain a tabular
format in the output. These goals are sometimes in conflict.
In the absence of the -f option (described above), the following
table describes the formats used for different ranges of numeric
values for any metric that is of type PM_TYPE_FLOAT or
PM_TYPE_DOUBLE, or any metric that has the semantics of a counter
(for which pmval reports the rate converted value):
┌───────────┬──────────────────────┐
│ Format │ Value Range │
├───────────┼──────────────────────┤
│ ! │ No values available │
│ 9.999E-99 │ < 0.1 │
│ 0.0 │ 0 │
│ 9.9999 │ > 0 and <= 0.9999 │
│ 9.999 │ > 0.9999 and < 9.999 │
│ 99.99 │ > 9.999 and < 99.99 │
│ 999.9 │ > 99.99 and < 999.9 │
│ 9999. │ > 999.9 and < 9999 │
│ 9.999E+99 │ > 9999 │
└───────────┴──────────────────────┘
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).
For environment variables affecting PCP tools, see
pmGetOptions(3).
PCPIntro(1), pmcd(1), pmchart(1), pmdumptext(1), pminfo(1),
pmlogdump(1), pmlogger(1), pmrep(1), pmtime(1), PMAPI(3),
pmSpecLocalPMDA(3), pmStore(3), pcp.conf(5), pcp.env(5) and
PMNS(5).
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 [email protected]. 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
[email protected]
Performance Co-Pilot PCP PMVAL(1)
Pages that refer to this page: pcpintro(1), pmafm(1), pmcd(1), pmchart(1), pmclient(1), pmdabash(1), pmdalogger(1), pmdapipe(1), pmdasystemd(1), pmie(1), pminfo(1), pmlogsummary(1), pmrep(1), pmstore(1), pmtime(1), pmregisterderived(3)
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HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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