LIKWID is developed by FAU for Performance Optimization, Modeling, and Architecture Analysis * Bringing the thinking back to the performance engineer. * Open-source * Command-line and Software Lib interface. No GUI * x86 Architecture (Intel & AMD) with initial support for Nvidia GPUs
LIKIWID Toolset is available in SCC as a module, thus before using LIKWID a user need to load their preferred LIKWID version module to set the environment correctly.
(base) gwdu101:25 17:17:18 ~ > module show likwid ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------- /opt/sw/modules/21.12/cascadelake/Core/likwid/5.2.0.lua: ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ... (base) gwdu101:25 17:17:24 ~ > (base) gwdu101:25 17:18:33 ~ > module load likwid (base) gwdu101:25 17:18:43 ~ >
The following tasks can be performed by LIKWID:
$ likwid-pin $ likwid-mpirun
$ likwid-features $ likwid-setFrequencies
* Using the available hardware counters to measure events that characterises the interaction between software and hardware * Uses a light-weight marker API for code instrumentation
$ likwid-perfctr
$ likwid-bench $ likwid-memsweeper
Examples of using “likwid-perfctr” on SCC's amp016 node
LIKWID_MARKER_INIT //global initialization LIKWID_MARKER_THREADINIT //individual thread initialization LIKWID_MARKER_START('compute') //Start a code region named 'compute' LIKWID_MARKER_STOP('compute') //Stop the code region named 'compute' LIWKID_MARKER_SWITCH //Switches perfromance group or event set in a round-robin fashion LIKWID_MARKER_CLOSE //global finalization