en:services:application_services:high_performance_computing:performance_engineering_and

Score-P

(Scalable Performance Measurement Infrustructure for Parallel codes) Is a powerful tool suite for profiling and tracing events during execution of parallel applications.

With its support for different data formats to instrument, write and read trace data, it supports a number of analyis tools including Vampir, Scalasca and TAU. Data formats supported by Score-P include, Open Trace format 2 - OTF2, Cube4 profilinf format and the Opari2 instrumenter.

To compile a code with Score-P, you have to load the module first then use the Score-P wrapper.

$ module load scorep

In our system, loading the Score-P module also enables links to both OTF2 and CUBE libraries.

For automatic instrumentation use the scorep wrapper before the compiler, for example

$# Environment variable setup examples

$ export SCOREP_ENABLE_TRACING=true

$ scorep --user gcc -c test.c -o test

For manual instrumentation the “–user” flag is added to the “scorep” command when compiling, i.e.

$ scorep --user gcc -o test test.c

The environment variable “SCOREP_ENABLE_TRACING” allows tracing measurements. Current Score-P environment variables currently set can be checked by “score-p-info”

$ scorep-info config-vars --full

#Output

SCOREP_ENABLE_PROFILING
Description: Enable profiling
      Type: Boolean
      Default: true

SCOREP_ENABLE_TRACING
Description: Enable tracing
      Type: Boolean
      Default: false

SCOREP_VERBOSE
Description: Be verbose
      Type: Boolean
      Default: false

 .....

To produce tace and profile files, just run the executable. NOTE: In SCC, unfortunately for libraries installed via Spack scorep module ought to be loaded at run-time for linking to the necessary data formats libraries, e.g. for an interactive mode…

module load scorep

# Then run the executable
$./test

Following is an example run-script for batch execution:

#!/bin/bash
#SBATCH --nodes=1
#SBATCH --partition=medium
#SBATCH --ntasks-per-node=16
#SBATCH --time=00:02:00
#SBATCH --job-name=vampir_trace_test
#SBATCH --output=traceTest_.%A_%a.out
#SBATCH --error=traceTest_e.%A_%a.err

module load scorep

export SCOREP_ENABLE_TRACING=true

# run the executable
srun ./trace.bin <input1, input2,...> output