VTune: Difference between revisions

Latest revision as of 17:18, 4 June 2021

Intel® VTune™ Profiler is an accurate performance analysis tool with low overhead for serial and multithreaded applications. Use VTune Profiler:

to determine the most time-consuming (hot) functions in your application
to discover on very fine-grained level which section of code (loop, source code line or even data field) do not effectively utilize available processor time
to analyse serial and multithreaded applications
- MPI (MPT, OpenMPI)
- OpenMP, Intel® oneAPI Threading Building Blocks, native threads
for applications developed in:
- C/C++/C#, Fortran, Python and others


Developer:	Intel
Platforms:	Hawk, Vulcan
Category:	Performance Analyzer
License:	Commercial
Website:	Intel® VTune™ Profiler homepage

Using Intel VTune

To perform the performance analyse of your application with VTune you don’t need special compiler wrapper or libraries. Just recompile and relink your code with extra –g option in order to include debug information. VTune works well for dynamically linked binaries. Here you can find some tips for statically linked binaries.

Example. Modules on Hawk:

module load vtune # set up VTune environment 
module load gcc mpt

Example. Modules on Vulcan:

module load performance/vtune/2020.1 # set up VTune environment 
module load mpi/openmpi/4.1.1-gnu-11.1.0

Compilation example:

mpicxx –O2 -g -Wl,-Bdynamic main.cpp

Run analysis

VTune has both a GUI and command line tool: vtune-gui and vtune. The following types of analysis are available on Hawk:

hotspots - Analyze application flow and identify sections of code that take a long time to execute (hotspots).
threading - Discover how well your application is using parallelism to take advantage of all available CPUs. Identify and locate synchronization issues causing overhead or idle wait time resulting in lost performance.
memory-consumption - Analyze memory consumption by your Linux application, its distinct memory objects and their allocation stacks.

IMPORTANT The VTune project working directory and the results directory must be placed on lustre FS.

Example for your job script:

..
module load vtune
module load gcc mpt
WORKDIR=/your/project/dir/on/lustre
cd ${WORKDIR}
mpirun -np 128  vtune -collect hotspots -r ${WORKDIR}/results_dir -- ./a.out your_input.file

Report

When VЕune completes the analysis, you can open the results in the vtune-gui tool. Alternatively you can also generate the report in text form using the VTune command line tool:

vtune -help report 
vtune -report summary -r ${WORKDIR}/results_dir

For some use cases you might need to limit the amount of raw data to be collected. Define this limit in MB through the data-limit option:

mpirun -np 128 vtune -collect hotspots -data-limit=200 -- ./a.out

Some more information about VTune you can find here.

External links

@@ Line 1: / Line 1: @@
 {{Infobox software
-| description = Intel® '''VTune™ Profiler ''' is a performance analysis tool for serial and multithreaded applications. Use VTune Profiler:
+| description = Intel® '''VTune™ Profiler ''' is an accurate performance analysis tool with low overhead for serial and multithreaded applications. Use VTune Profiler:
 * to determine the most time-consuming (hot) functions in your application
 * to discover on very fine-grained level which section of code (loop, source code line or even data field) do not effectively utilize available processor time
-* to analyse communication behavior that affects threaded performance
+* to analyse serial and multithreaded applications
-* for accurate analysis with low overhead
-* for serial and multithreaded applications
 **	MPI (MPT, OpenMPI)
 **	OpenMP, Intel® oneAPI Threading Building Blocks, native threads
-*	Languages:
+* for applications developed in:
 **	C/C++/C#, Fortran, Python and others
@@ Line 20: / Line 18: @@
 === Using Intel VTune ===
-To perform the performance analyse of your application with VTune you don’t need special compiler wrapper or libraries. Just recompile and relink your code with extra –g option in order to include debug information. VTune works well for dynamically linked binaries. [https://software.intel.com/content/www/us/en/develop/documentation/vtune-help/top/set-up-analysis-target/linux-targets/analyzing-statically-linked-binaries-on-linux-targets.html Here] you can find some tips for statically linked binaries
+To perform the performance analyse of your application with VTune you don’t need special compiler wrapper or libraries. Just recompile and relink your code with extra –g option in order to include debug information. VTune works well for dynamically linked binaries. [https://software.intel.com/content/www/us/en/develop/documentation/vtune-help/top/set-up-analysis-target/linux-targets/analyzing-statically-linked-binaries-on-linux-targets.html Here] you can find some tips for statically linked binaries.
-Example:
+Example. Modules on Hawk:
 <pre>
-module load compiler/intel
+module load vtune # set up VTune environment
-module load performance/vtune # set up VTune environment
+module load gcc mpt
-module load mpi/impi          # if MPI needed
 </pre>
-Compilation example:
+Example. Modules on Vulcan:
 <pre>
-ifort -g -O2 prog.f90
+module load performance/vtune/2020.1 # set up VTune environment
+module load mpi/openmpi/4.1.1-gnu-11.1.0
 </pre>
-Analyzing MPI applications:
+Compilation example:
 <pre>
- mpirun –n4 amplxe-cl -c hotspots –r my_result -- path_to_my_app
+mpicxx –O2 -g -Wl,-Bdynamic main.cpp
 </pre>
-=== Using Intel VTune on Cray machines ===
+'''Run analysis'''
-Load the necessary module. For example:
+VTune has both a GUI and command line tool: vtune-gui and vtune.
+The following types of analysis are available on Hawk:
+* ''hotspots'' - Analyze application flow and identify sections of code that take a long time to execute (hotspots).
+* ''threading'' - Discover how well your application is using parallelism to take advantage of all available CPUs. Identify and locate synchronization issues causing overhead or idle wait time resulting in lost performance.
+* ''memory-consumption'' - Analyze memory consumption by your Linux application, its distinct memory objects and their allocation stacks.
+'''IMPORTANT''' ''The VTune project working directory and the results directory must be placed on lustre FS.''
+Example for your job script:
 <pre>
-module swap PrgEnv-cray PrgEnv-intel # set up MPI environment too
+..
-module load performance/vtune        # set up VTune environment
+module load vtune
+module load gcc mpt
+WORKDIR=/your/project/dir/on/lustre
+cd ${WORKDIR}
+mpirun -np 128  vtune -collect hotspots -r ${WORKDIR}/results_dir -- ./a.out your_input.file
 </pre>
-Compilation example:
+'''Report'''
+When VЕune completes the analysis, you can open the results in the vtune-gui tool. Alternatively you can also generate the report in text form using the VTune command line tool:
 <pre>
-ftn -dynamic -g -O2 prog.f90
+vtune -help report
+vtune -report summary -r ${WORKDIR}/results_dir
 </pre>
-Analyzing MPI applications:
+For some use cases you might need to limit the amount of raw data to be collected. Define this limit in MB through the data-limit option:
 <pre>
- aprun –n4 amplxe-cl -c hotspots –r myResult-@@@{at} -- path_to_my_app
+mpirun -np 128 vtune -collect hotspots -data-limit=200 -- ./a.out
 </pre>
+Some more information about VTune you can find [https://kb.hlrs.de/platforms/upload/Vtune_perf_analysis.pdf here].
 == See also ==
@@ Line 60: / Line 76: @@
 == External links ==
-* [http://software.intel.com/en-us/intel-vtune/ Intel® VTune™ Amplifier XE homepage]
+* [https://software.intel.com/content/www/us/en/develop/tools/oneapi/components/vtune-profiler.html Intel® VTune™ Profiler homepage]
+* [https://software.intel.com/content/www/us/en/develop/documentation/vtune-help/top/introduction.html Introduction to Intel® VTune™ Profiler]
 [[Category:Performance Analyzer]]

VTune: Difference between revisions

Latest revision as of 17:18, 4 June 2021

Using Intel VTune

See also

External links

Navigation menu

Page actions

Page actions

Personal tools

Navigation

Search

Tools