Umpire Tutorial

This section is a tutorial introduction to Umpire. We start with the most basic memory allocation, and move through topics like allocating on different resources, using allocation strategies to change how memory is allocated, using operations to move and modify data, and how to use Umpire introspection capability to find out information about Allocators and allocations.

These examples are all built as part of Umpire, and you can find the files in the examples directory at the root of the Umpire repository. Feel free to play around and modify these examples to experiment with all of Umpire’s functionality.

The following tutorial examples assume a working knowledge of C++ and a general understanding of how memory is laid out in modern heterogeneous computers. The main thing to remember is that in many systems, memory on other execution devices (like GPUs) might not be directly accessible from the CPU. If you try and access this memory your program will error! Luckily, Umpire makes it easy to move data around, and check where it is, as you will see in the following sections.

We also have a tutorial for the C interface to Umpire. Complete example listings are available, and will be compiled if you have configured Umpire with -DUMPIRE_ENABLE_C=On.

The C tutorial assumes an understanding of C, and it would be useful to have some knowledge of C++ to understand how the C API maps to the native C++ classes that Umpire provides.

Finally, we have a tutorial for Umpire’s FORTRAN API. These examples will be compiled when configuring with -DENABLE_FORTRAN=On. The FORTRAN tutorial assumes an understanding of FORTRAN. Familiarity with the FORTRAN’s ISO C bindings can be useful for understanding why the interface looks the way it does.