Plugin_variorum_sampler 

Date:: 27 Jun 2022

NAME 

Plugin_variorum_sampler - man page for the LDMS Variorum plugin

SYNOPSIS 

Within ldmsd_controller or a configuration file:

config name=variorum_sampler [common attributes]

With LDMS (Lightweight Distributed Metric Service), plugins for the ldmsd (ldms daemon) are configured via ldmsd_controller or a configuration file. The variorum_sampler plugin provides power data using the JSON API in Variorum, a vendor-neutral library that provides access to low-level hardware knobs. The sampler, when configured, automatically detects the number of sockets on the host machine and then provides, for each socket, an LDMS record containing power data. For each socket, the values provided are: node power consumption in Watts (identical across sockets); socket ID number; CPU power consumption in Watts; GPU power consumption in Watts (aggregated across all GPUs on the socket, and reported as -1 on unsupported platforms); and memory power consumption in Watts.

The variorum sampler depends on Variorum 0.6.0 or higher and Jansson. The sampler cannot be built without these libraries. If either library is installed in a non-standard location, paths to the respective install directories should be provided to Autoconf using the –with-libjansson-prefix and/or –with-libvariorum-prefix flag.

CONFIGURATION ATTRIBUTE SYNTAX 

The variorum sampler plugin uses the sampler_base base class. This man page covers only the configuration attributes, or those with default values, specific to the this plugin; see ldms_sampler_base.man for the attributes of the base class.

config

name=<plugin_name> exclude_ports=<devs>

configuration line

name=<plugin_name>: This MUST be variorum_sampler.
schema=<schema>: Optional schema name. It is intended that the same sampler on different nodes with different metrics have a different schema. If not specified, will default to `variorum_sampler`.

BUGS 

No known bugs; however, if Variorum cannot access the hardware knobs, the sampler will be unable to access any data. This will result in an error being printed to the log file: “variorum_sampler: unable to obtain JSON object data”. This error can be resolved by ensuring that hardware knob access is enabled using the requirements here: https://variorum.readthedocs.io/en/latest/HWArchitectures.html

EXAMPLES 

Within ldmsd_controller or a configuration file:

load name=variorum_sampler
config name=variorum_sampler producer=vm1_1 instance=vm1_1/variorum_sampler
start name=variorum_sampler interval=1000000

AUTHORS 

Jessica Hannebert <j_hannebert@coloradocollege.edu> (Colorado College, internship at Lawrence Livermore National Laboratory). Tapasya Patki <patki1@llnl.gov> (Lawrence Livermore National Laboratory). Kathleen Shoga <shoga1@llnl.gov> (Lawrence Livermore National Laboratory). Stephanie Brink <brink2@llnl.gov> (Lawrence Livermore National Laboratory). Barry Rountree <rountree4@llnl.gov> (Lawrence Livermore National Laboratory).