# kokkos-tutorials

**Repository Path**: ca1ic0/kokkos-tutorials

## Basic Information

- **Project Name**: kokkos-tutorials
- **Description**: No description available
- **Primary Language**: C++
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2023-11-13
- **Last Updated**: 2023-11-13

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

![Kokkos](https://avatars2.githubusercontent.com/u/10199860?s=200&v=4)

# Kokkos Tutorials

This repository contains tutorials for the Kokkos C++ programming
model (github.com/kokkos/kokkos). 

Tutorials in the **Intro-Short** directory cover
 * simple data parallel patterns and policies
 * multidimensional array views
 * execution and memory spaces

Tutorials in the **Intro-Full** directory cover
 * simple data parallel patterns and policies
 * multidimensional array views
 * execution and memory spaces
 * thread safety and atomic operations
 * hierarchical data parallel patterns

# Building the Tutorials

All the tutorial folders can be built using either the `Makefile` or the CMake `CMakeLists.txt` file in each folder.

## Makefiles

The raw Makefiles require Makefile variables to be properly configured. 
In most examples, this is `KOKKOS_PATH` pointing to the Kokkos source directory
and `KOKKOS_DEVICES` which contains the list of device backends to build.
This will build a new Kokkos library for each exercise.

## CMake + Spack

The CMake files build against an installed Kokkos library. 
The easiest way to do this is using Spack.
There is a `spack.sh` script that automates most of this.
The Spack script can be run in any excercise folder with a `CMakeLists.txt`.

````
../../BuildScripts/spack.sh +openmp %gcc@7.3.0
````
This will make sure Kokkos is installed with the OpenMP backend for the GCC 7.3.0 compiler.
It will then configure CMake and create a `spack-build` folder where `make` can be run.
The `spack.sh` accepts the full list of variants and specs as the parent Kokkos package,
which can be viewed by running:

````
spack info kokkos
````

The `spack.sh` script uses the special DIY mode of Spack to install dependencies and configure the current source folder to build.

For Kokkos Kernels tutorials, there is similarly a `kk-spack.sh` script, e.g.
````
../../BuildScripts/kk-spack.sh +openmp %gcc@7.3.0 ^kokkos+aggressive_vectorization
````
All the arguments to the script get passed as a spec for the tutorial.
We are indirectly configuring Kokkos, hence the `^` notation for specifying the exact Kokkos dependency spec.