Package Managers

Use your favorite package manager to install Kokkos.

System package managers

DNF

You may use the Fedora Project package manager to install Kokkos https://packages.fedoraproject.org/pkgs/kokkos/

Other package managers

Spack

Spack is a popular package manager for HPC. Spack comes with installation recipes for Kokkos.

The Kokkos recipe webpage summarizes the available versions of Kokkos and their options.

Most of the time, Spack Kokkos’ variants follow the same options as the Kokkos CMake options. List of available variants can be found by running

spack info kokkos

When using Spack, Kokkos hardware autodetection is disabled. That means that the user always has to manually specify the architecture. However, for CPU, Spack already specify the CPU micro-architecture, so it is not needed to specify it again. For GPU, no such mecanism exists in Spack and the user always need to specify the correct architecture, using a dedicated backend keyword (see next section).

Installing Kokkos with Spack

To install Kokkos with Spack with default options, run:

spack install kokkos

To install Kokkos with CUDA backend enabled, run:

spack install kokkos +cuda cuda_arch=90

Note that the cuda_arch option is specific to the target GPU architecture. Here, the cuda_arch value 90 corresponds to the NVIDIA Hopper architecture. With Spack, the architecture must be specified explicitly (no auto-detection).

For AMD GPU, the traditional Spack’s keyword is rocm instead of hip in Kokkos’ CMake. So to install Kokkos with the HIP backend enable, run:

spack install kokkos +rocm amdgpu_target=gfx942

Note that the amdgpu_target option is specific to the target GPU architecture. With Spack, the architecture must be specified explicitly (no auto-detection).

For Intel GPU, using the SYCL backend, run:

spack spec kokkos +sycl intel_gpu_arch=intel_pvc

Note that the intel_gpu_arch option is specific to the target GPU architecture. With Spack, the architecture must be specified explicitly (no auto-detection).

To use the installed Kokkos, you can simply load the Kokkos module:

spack load kokkos

This will inject the Kokkos environment into your shell session.

Packaging your own Kokkos dependent project with Spack

Let’s say you have a project Foo that depends on Kokkos. You can package your project with Spack and include Kokkos as a dependency.

You have to create a recipe that is contained in a file named package.py in the foo directory of your recipe repository. You can package as usual with Spack (for example, you can follow the packaging tutorial), but you have to take into account that for certain backends, you might need to specify the compiler to use.

The compiler might be a wrapper, like nvcc_wrapper for CUDA. It is exported by the Kokkos package as the kokkos_cxx attribute.

Here is an example of a package.py file that includes Kokkos as a dependency:

from spack.package import *

class Foo(CMakePackage):
    # Usual description of a Spack package

    depends_on("kokkos")

    def cmake_args(self):
        args = []
        # Ensure that the proper compiler is used
        # It might be nvcc_wrapper
        args.append(self.define("CMAKE_CXX_COMPILER", self["kokkos"].kokkos_cxx))
        return args

For more complete examples, you can look at already existing recipes in the Required by section of Kokkos Spack recipe or by running:

spack dependents kokkos