OpenMP for GPU offloading

This course is intended for newcomers to OpenMP GPU offloading. By the end of it, students will feel comfortable with the basic process of introducing OpenMP offloading constructs to a simple code base. They will then be able to

• reason about which parts of the code to change,

• know how to manage data transfers, lifetimes and reductions,

• use a mini-app to observe behavior

• be aware of how to interact with GPU libraries

• be aware of how to interact with MPI

Prerequisites

• Understanding of how to read either C++ or Fortran code

• Running programs from a terminal command line

• For one lesson, familiarity with MPI concepts for multi-node programming

20 min	Why OpenMP offloading?
40 min	Heat diffusion mini-app
40 min	Introduction to GPU architecture
60 min	Profiling code for GPUs
40 min	Offloading to GPU
40 min	Data environment
40 min	Working alongside GPU libraries
60 min	Multiple GPUs
40 min	Working alongside GPU libraries
40 min	Porting code to OpenMP offloading

The lessons

• Why OpenMP offloading?
• Heat diffusion mini-app
• Introduction to GPU architecture
• Profiling code for GPUs
• Offloading to GPU
• Data environment
• Optimizing OpenMP offloaded code
• Multiple GPUs
• Working alongside GPU libraries
• Porting code to OpenMP offloading

Reference

• Quick Reference
• Instructor’s guide
• Preparing to Teach

Who is the course for?

This course is for all people who seek to understand the basics of how OpenMP offloading for GPUs can improve the performance of their code.

About the course

This course is offered jointly by ENCCS (https://enccs.se/) and CSC (https://www.csc.fi/)

See also

https://github.com/OpenMP/Examples https://github.com/UoB-HPC/openmp-tutorial

Credits

The lesson file structure and browsing layout is inspired by and derived from work by CodeRefinery licensed under the MIT license. We have copied and adapted most of their license text.

Instructional Material

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With the understanding that:

• You do not have to comply with the license for elements of the material in the public domain or where your use is permitted by an applicable exception or limitation.

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Software

Except where otherwise noted, the example programs and other software provided with this repository are made available under the OSI-approved MIT license.