How to enable the GPU to run a FORTRAN program?

[eliopoulos]

How can I enable the GPU to run a parallel do loop in a FORTRAN program? I have tried: "!$omp target teams distribute parallel do" but the GPU does not run. Any advice?

[Barbara_P_Intel]

Which Fortran compiler are you using?

How are you compiling? 

Have you seen this article?

Here's a tutorial. 

[eliopoulos]

Thank you. I have installed Intel oneapi 2021 base and HPC toolkit. I have compiled using: Generate Parallel Code (/Qopenmp). I shall read the article and the tutorial.

[Barbara_P_Intel]

I suggest you install the oneAPI 2024 release of Base and HPC Toolkits. Those were released in November 2023 with new features and bug fixes.

[eliopoulos]

I have a problem with that. I cannot uninstall the current version. I press uninstall and then remove and it does nothing.

[Devorah_H_Intel]

---

@eliopoulos wrote:

I have a problem with that. I cannot uninstall the current version. I press uninstall and then remove and it does nothing.

---

Please report the details of uninstallation and installation issue in this forum https://community.intel.com/t5/oneAPI-Registration-Download/bd-p/registration-download-licensing-instal 

[Barbara_P_Intel]

Here's another article on using OpenMP directives to offload to Intel GPUs.

[eliopoulos]

I get the warning: '/Qopenmp-targets:spir64' not supported. Is it the Intel oneapi version I use or something else?

[Barbara_P_Intel]

Can you please post your link command?

[eliopoulos]

I don't link by command. I just write in the command line: /Qxhost /Qopenmp /Qopenmp-targets:spir64 and I build the solution.

[Barbara_P_Intel]

Are you using ifx? GPUs are not supported with ifort.

[eliopoulos]

I don't know. How can I use ifx?

[eliopoulos]

Ok, I used ifx and I get:

Severity Code Description Project File Line Suppression State
Error error LNK2019: unresolved external symbol __tgt_target_teams_mapper referenced in function MAIN__ BSFADAS_03.obj
Error error LNK2019: unresolved external symbol __tgt_push_code_location referenced in function MAIN__ BSFADAS_03.obj
Error fatal error LNK1120: 2 unresolved externals x64\Release\BSFADAS_03.exe

[eliopoulos]

When I link using the command: 

ifx /Qxhost /Qopenmp /Qopenmp-targets:spir64 /Qmkl bsfadas_03.for

I get:

1882084.obj : warning LNK4078: multiple '__CLANG_OFFLOAD_BUNDLE__openmp-s' sections found with different attributes (40100800)

1882084.obj : warning LNK4078: multiple '__CLANG_OFFLOAD_BUNDLE_SIZE__ope' sections found with different attributes (40100800)

and when I run the program:

Libomptarget error: Unable to generate entries table for device id 0.
Libomptarget error: Failed to init globals on device 0
Libomptarget error: Failed to get device 0 ready
Libomptarget error: run with env LIBOMPTARGET_INFO>1 to dump host-target pointer maps
Libomptarget error: Build with debug information to provide more informationLibomptarget fatal error 1: failure of target construct while offloading is mandatory

[Barbara_P_Intel]

Have you been able to run a code that doesn't use MKL successfully? I'm just trying to keep this simple to start.

[eliopoulos]

I have tried a simple code I found in one of your articles and produces the same warnings. The program runs but the GPU is not enabled.

[Barbara_P_Intel]

Yes, you need a GPU driver installed. I don't use the GPU in my laptop. But, be aware, most of the Intel GPUs on laptops only support 32 reals. 

For Windows here's a link to Intel GPU drivers. And another one for older Intel GPUs.

Are you aware of the Intel Developer Cloud? You can get free access to Intel CPU/GPU on Linux.

[eliopoulos]

I have already installed the latest driver (version 31.0.101.5186) of my Intel iris xe graphics GPU.

[eliopoulos]

I have uninstalled the previous versions and installed Visual Studio 2022 Enterprise and Intel oneapi 2024 base and HPC toolkit but nothing changed. Only Intel GPU are compatible with FORTRAN?

[Barbara_P_Intel]

What version of Windows are you using? Are you running from VS or Command window? Can you try the other?

This seems like an environment issue. I don't have access to Iris xe graphics on Windows to test.

[eliopoulos]

I use Windows 11 Pro. I run from the Command window. I shall try the other.