Ubuntu Manpage: pmstore - modify performance metric values

NAME

       pmstore - modify performance metric values

SYNOPSIS

       pmstore [-LfF] [-h host] [-i instances] [-K spec] [-n pmnsfile] metricname value

DESCRIPTION

Under certain circumstances, it is useful to be able to modify the values of performance
metrics, for example to re-initialize counters or to assign new values to metrics that act
as control variables.

pmstore changes the current values for the nominated instances of a single performance
metric, as identified by metricname and the list of instance identifiers following the -i
argument. instances must be a single argument, with elements of the list separated by
commas and/or white space. By default all instances of metricname will be updated.

Normally pmstore operates on the default Performance Metrics Name Space (PMNS), however if
the -n option is specified an alternative namespace is loaded from the file pmnsfile.

Unless directed to another host by the -h option, pmstore will interact with the
Performance Metric Collector Daemon (PMCD) on the local host.

The -L option causes pmstore to use a local context to store to metrics from PMDAs on the
local host without PMCD. Only some metrics are available in this mode. The -h and -L
options are mutually exclusive.

The -f option forces the given value to be stored, even if there is no current value set.

The interpretation of value is dependent on the syntax used in its specification and the
underlying data type of metricname, as follows.

1. If the metric has an integer type, then value should be an optional leading hyphen,
followed either by decimal digits or ``0x'' and some hexadecimal digits. ``0X'' is
also acceptable in lieu of ``0x''. See strtol(3) and the related routines.

2. If the metric has a floating point type, then value should be either in the form of an
integer described above, or a fixed point number, or a number in scientific notation.
See strtod(3).

3. If the metric has a string type, then value is interpreted as a literal string of
ASCII characters.

4. If the metric has any other type (i.e. PM_TYPE_EVENT or PM_TYPE_AGGREGATE) then no
encoding of value from the command line makes sense, and the values of these metrics
cannot be modified with pmstore.

The output reports the old value and the new value for each updated instance of the
requested metric.

When using the -L option to fetch metrics from a local context, 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.

Normally pmstore will report the old value (as initially retrieved using pmFetch(3)) and
the new value from the command line. The -F option forces another pmFetch(3) after the
pmStore(3) and the returned value is reported as the new value. This is useful in cases
where metricname is a metric that provides different semantics for the store operation,
e.g. to increment the current value or reset a counter (independent of the value from the
command line).

FILES

       $PCP_VAR_DIR/pmns/*
                 default PMNS specification files

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).

DIAGNOSTICS