pmtrace (1) - Linux Manuals

pmtrace: command line performance instrumentation

NAME

pmtrace - command line performance instrumentation

SYNOPSIS

pmtrace [-q] [-c value | -e command | -v value] [-h host] [-S state] tag

DESCRIPTION

pmtrace provides a simple command line interface to the trace Performance Metrics Domain Agent (PMDA) and the associated pcp_trace library.

The default pmtrace behavior is to provide point trace data to the trace PMDA, using the tag argument as the identifying name associated with each trace point. The tag then becomes an instance identifier within the set of trace.point metrics.

The -e option allows an arbitrary command to be executed. This command will be measured as a transaction since it has well defined start and end points. The information is made available through the trace.transact metrics.

Trace data can be sent to the trace PMDA running on host, rather than the localhost, using the -h option. This overrides use of the environment variable PCP_TRACE_HOST.

The -q option suppresses messages from a successful trace, so that pmtrace runs quietly.

The -c option allows an arbitrary counter value to be exported through the trace.count metrics, while the -v option allows an arbitrary floating point value to be exported through the trace.observe metrics

The -S option enables internal debugging and tracing. The value of state is a bit-wise combination of debug flags as defined in pmtracestate(3), and may be specified using the decimal or hexadecimal syntax prescribed by strtol(3).

ENVIRONMENT

Since pmtrace uses the libpcp_trace library routines, the environment variables PCP_TRACE_HOST, PCP_TRACE_PORT, and PCP_TRACE_TIMEOUT are all honored. Refer to pmdatrace(3) for a detailed description of the semantics of each.

FILES

$PCP_DEMOS_DIR/trace/pmtrace.c

source code for pmtrace

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

All are generated on standard error and are intended to be self-explanatory.

The pmtrace exit status is always zero except when the -e option is in use, in which case the exit status of command is returned.