NAME¶
pmdasystemtap - Systemtap performance metrics domain agent (PMDA)
DESCRIPTION¶
pmdasystemtap is a Performance Metrics Domain Agent (PMDA) which exports
metric values from the Linux Systemtap dynamic tracing toolkit.
This implementation uses the
stap(1) tool, which is a front-end to the
Systemtap toolkit.
INSTALLATION¶
In order to access performance data exported by Systemtap from with PCP, it is
necessary to perform two configuration steps:
- 1.
- Configure Systemtap probes, and verify them with stap(1). These
should be produced in a format that is easily parsed, and then stored in
the $PCP_PMDAS_DIR/systemtap/probes.stp file.
- 2.
- Configure pmdasystemtap to extract the values from the text
produced by stap. Two example probes are implemented in the default
systemtap PMDA script - readdir and sync traces (see
$PCP_PMDAS_DIR/systemtap/pmdasystemtap.pl for details).
# cd $PCP_PMDAS_DIR/systemtap
# [ edit probes.stp, test /usr/bin/stap probes.stp ]
# [ edit pmdasystemtap.pl ]
Once this is setup, you can access the names and values for the systemtap
performance metrics by doing the following as root:
# cd $PCP_PMDAS_DIR/systemtap
# ./Install
If you want to undo the installation, do the following as root:
# cd $PCP_PMDAS_DIR/systemtap
# ./Remove
pmdasystemtap 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_PMDAS_DIR/systemtap/probes.stp
- probe configuration file for stap(1), run by
pmdasystemtap
- $PCP_PMDAS_DIR/systemtap/Install
- installation script for the pmdasystemtap agent
- $PCP_PMDAS_DIR/systemtap/Remove
- undo installation script for the pmdasystemtap agent
- $PCP_LOG_DIR/pmcd/systemtap.log
- default log file for error messages from pmdasystemtap
SEE ALSO¶
pmcd(1) and
stap(1).