Building

KokkosKernels is a stand-alone library in the Kokkos Ecosystem, as well as a package within the Trilinos Project

Building KokkosKernels as a stand-alone library requires CMake. Using KokkosKernels as a package within Trilinos additionally requires the TriBITS build system.

General Requirements:

Compatible versions of Kokkos and Kokkos Kernels cloned or downloaded from https://github.com
Supported compiler and computing hardware - see Kokkos' README for what is currently tested.
CUDA builds require use of the nvcc_wrapper script provided by Kokkos, unless using Clang-CUDA

Basic steps for building stand-alone Kokkos Kernels:

Create a build directory <BUILD_DIR> (different from source and install locations).

> mkdir <BUILD_DIR>
cd <BUILD_DIR>

Run cmake ${SOURCE_DIR} <...> where SOURCE_DIR is the location of the Kokkos Kernels source. <...> is a list of CMake options given as `-D{OPTION}={VALUE}'
Build and install the library, depending on the generator (make is default):

> make install

or

> ninja install

To use the Ninja build system add -G Ninja.

A full listing of CMake options is given below. Another way to get a list of options and documentation is to the use ccmake utility.

ccmake <SOURCE_DIR>

which brings up a user interface listing all the options, their default values, and associated documentation.

Sample CMake

Below is a list of example CMake configurations. Kokkos Kernels requires first building Kokkos (or including it as a subproject). To see a full list of options for building Kokkos, see BUILD

OpenMP backend, g++ compiler, Intel Skylake architecture:

First install Kokkos:

> cmake \
  -DCMAKE_CXX_COMPILER=g++ \
  -DCMAKE_INSTALL_PREFIX=${HOME}/kokkos-install \
  -DKokkos_ENABLE_OPENMP=ON \
  -DKokkos_ARCH_SKX=ON \
  <KOKKOS_SOURCE>
> make install

Then build Kokkos Kernels, pointing to Kokkos:

> cmake \
  -DKokkos_ROOT=${HOME}/kokkos-install \
  -DCMAKE_CXX_COMPILER=g++ 
  <KOKKOS_KERNELS_SOURCE>
> make

Cuda and Serial backends, nvcc_wrapper compiler, Power8 and Volta sm_70 architectures, various compilation flags

First install Kokkos:

> cmake \
  -DCMAKE_CXX_COMPILER=<KOKKOS_SOURCE>/bin/nvcc_wrapper \
  -DCMAKE_INSTALL_PREFIX=${HOME}/kokkos-install \
  -DKokkos_ENABLE_CUDA=ON \
  -DKokkos_ENABLE_SERIAL=ON \
  -DKokkos_ARCH_VOLTA70=ON \
  -DKokkos_ARCH_POWER8=ON \
  <KOKKOS_SOURCE>
> make install

Then build Kokkos Kernels, pointing to Kokkos:

> cmake \
  -DKokkos_ROOT=${HOME}/kokkos-install \
  -DCMAKE_CXX_COMPILER=${HOME}/kokkos-install/bin/nvcc_wrapper \
  <KOKKOS_KERNELS_SOURCE>
> make

If you wish to enable certain CUDA third-party libraries (TPLs), you can also configure with

> cmake \
  -DKokkos_ROOT=${HOME}/kokkos-install \
  -DCMAKE_CXX_COMPILER=${HOME}/kokkos-install/bin/nvcc_wrapper \
  -DKokkosKernels_ENABLE_TPL_CUSPARSE=ON \
  <KOKKOS_KERNELS_SOURCE>

Required

CMake >= 3.10
Compatible compiler and hardware

Trilinos

If building with Trilinos, the same set of CMake options apply. The only difference is you must enable KokkosKernels:

  cmake \
    -D Trilinos_ENABLE_KokkosKernels:BOOL=ON \
  ...

Running tests:

Note, no tests will be available unless -DKokkosKernels_ENABLE_TESTS=ON is in your cmake command. To run the tests, simply execute a CMake build and then run:

> make test

To limit the tests, one can cd into either unit_test or perf_test and also run make test. To show full detail of all tests, you can run ctest --extra-verbose. You can filter exactly which tests are run based on regular expressions with

ctest -R <match_string>

Tests are grouped into individual executables. You can run the executable for one of the enabled backends based on your configuration, for example if OpenMP is enabled:

>./KokkosKernels_UnitTest_OpenMP

To run a specific test in the executable use the --gtest_filter flag:

>./KokkosKernels_UnitTest_OpenMP --gtest_filter=openmp.dot_double`

Kokkos Kernels CMake Option Listing

Test Options

KokkosKernels_ENABLE_TESTS: BOOL
- Whether to build tests.
- Default: OFF
KokkosKernels_TEST_ETI_ONLY: BOOL
- Whether to restrict testing to ETI types.
- Default: ON
KokkosKernels_ENABLE_PERFTESTS: STRING
- Whether to build performance tests
- Default: OFF
KokkosKernels_ENABLE_TESTS_AND_PERFSUITE: BOOL
- Whether to build performance tests and suite.
- Default: OFF

Examples Options

KokkosKernels_ENABLE_EXAMPLES: BOOL
- Whether to build examples.
- Default: OFF

Component Options

KokkosKernels_ENABLED_COMPONENTS: BOOL
- A list of components to enable in testing and building
- Default: ALL
- Valid: BATCHED BLAS LAPACK GRAPH SPARSE ALL
KokkosKernels_ENABLE_ALL_COMPONENTS: BOOL
KokkosKernels_ENABLE_BATCHED: BOOL
KokkosKernels_ENABLE_BLAS: BOOL
KokkosKernels_ENABLE_LAPACK: BOOL
KokkosKernels_ENABLE_SPARSE: BOOL
KokkosKernels_ENABLE_GRAPH: BOOL
KokkosKernels_ENABLE_ODE: BOOL

ETI Options

KokkosKernels_INST_HALF: BOOL
- Whether to pre instantiate kernels for the scalar type Kokkos::Experimental::half_t. Disabling this may increase build times
- Default: OFF
KokkosKernels_INST_BHALF: BOOL
- Whether to pre instantiate kernels for the scalar type Kokkos::Experimental::bhalf_t. Disabling this may increase build times
- Default: OFF
KokkosKernels_ETI_ONLY: BOOL
- Whether to restrict availability of kernels to ETI types only. Turning this on guarantees that kernels are never built inside of object files which simply call KokkosKernels functions.
- Default: OFF
KokkosKernels_INST_COMPLEX_DOUBLE: BOOL
- Whether to pre instantiate kernels for the scalar type complex. Disabling this may increase build times.
- Default: OFF or unless enabled during a Trilinos build with Trilinos_ENABLE_COMPLEX_DOUBLE.
KokkosKernels_INST_COMPLEX_FLOAT: BOOL
- Whether to pre instantiate kernels for the scalar type complex. Disabling this may increase build times.
- Default: OFF or unless enabled during a Trilinos build with Trilinos_ENABLE_COMPLEX_FLOAT.
KokkosKernels_INST_DOUBLE: BOOL
- Whether to pre instantiate kernels for the scalar type double. This option is KokkosKernels_INST_DOUBLE=ON by default. Disabling this may increase build times.
- Default: ON
KokkosKernels_INST_EXECSPACE_OPENMP: BOOL
- Whether to pre instantiate kernels for the execution space Kokkos::OpenMP. Disabling this when Kokkos_ENABLE_OpenMP is enabled may increase build times.
- Default: ON if Kokkos is OpenMP-enabled, OFF otherwise.
KokkosKernels_INST_EXECSPACE_SERIAL: BOOL
- Whether to build kernels for the execution space Kokkos::Serial. If explicit template instantiation (ETI) is enabled in Trilinos, disabling this when Kokkos_ENABLE_SERIAL is enabled may increase build times.
- Default: ON when Kokkos is Serial-enabled, OFF otherwise.
KokkosKernels_INST_EXECSPACE_THREADS: BOOL
- Whether to build kernels for the execution space Kokkos::Threads. If explicit template instantiation (ETI) is enabled in Trilinos, disabling this when Kokkos_ENABLE_PTHREAD is enabled may increase build times.
- Default: ON if Kokkos is Threads-enabled, OFF otherwise.
KokkosKernels_INST_FLOAT: BOOL
- Whether to pre instantiate kernels for the scalar type float. Disabling this may increase build times.
- Default: OFF or unless enabled during a Trilinos build with Trilinos_ENABLE_FLOAT.
KokkosKernels_INST_LAYOUTLEFT: BOOL
- Whether to pre instantiate kernels for the view layout LayoutLeft. This option is KokkosKernels_INST_LAYOUTLEFT=ON by default. Disabling this may increase build times.
- Default: ON
KokkosKernels_INST_LAYOUTRIGHT: BOOL
- Whether to pre instantiate kernels for the view layout LayoutRight. This option is KokkosKernels_INST_LAYOUTRIGHT=OFF by default. Disabling this may increase build times.
- Default: OFF
KokkosKernels_INST_MEMSPACE_HOSTSPACE: BOOL
- Whether to pre instantiate kernels for the memory space Kokkos::HostSpace. Disabling this when one of the Host execution spaces is enabled may increase build times.
- Default: ON
KokkosKernels_INST_OFFSET_INT: BOOL
- Whether to pre instantiate kernels for the offset type int. This option is KokkosKernels_INST_OFFSET_INT=ON by default.
- Default: ON
KokkosKernels_INST_OFFSET_SIZE_T: BOOL
- Whether to pre instantiate kernels for the offset type size_t. This option is KokkosKernels_INST_OFFSET_SIZE_T=OFF by default.
- Default: ON
KokkosKernels_INST_ORDINAL_INT: BOOL
- Whether to pre instantiate kernels for the ordinal type int. This option is KokkosKernels_INST_ORDINAL_INT=ON by default.
- Default: ON
KokkosKernels_INST_ORDINAL_INT64_T: BOOL
- Whether to pre instantiate kernels for the ordinal type int64_t. This option is KokkosKernels_INST_ORDINAL_INT64_T=OFF by default.
- Default: OFF
KokkosKernels_ADD_DEFAULT_ETI: BOOL
- Whether to include a set of default ETI instantiations (otherwise only those explicitly requested will be included
- Default: OFF
KokkosKernels_INST_EXECSPACE_CUDA: BOOL
- Whether to pre instantiate kernels for the execution space Kokkos::Cuda. Disabling this when Kokkos_ENABLE_CU DA is enabled may increase build times.
- Default: ON if Kokkos is CUDA-enabled, OFF otherwise
KokkosKernels_INST_MEMSPACE_CUDAUVMSPACE: BOOL
- Whether to pre instantiate kernels for the memory space Kokkos::CudaUVMSpace. Disabling this when Kokkos_ENA BLE_CUDA is enabled may increase build times.
- Default: OFF.
KokkosKernels_INST_EXECSPACE_HIP: BOOL
KokkosKernels_INST_MEMSPACE_HIPSPACE: BOOL
KokkosKernels_INST_EXECSPACE_SYCL: BOOL
KokkosKernels_INST_MEMSPACE_SYCLSPACE: BOOL
KokkosKernels_INST_EXECSPACE_OPENMPTARGET: BOOL
KokkosKernels_INST_MEMSPACE_OPENMPTARGETSPACE: BOOL
KokkosKernels_INST_MEMSPACE_HBWSPACE: BOOL

Documentation Options

KokkosKernels_ENABLE_DOCS: BOOL
- Whether to build documentation
- Default: OFF

Supported Third-party Libraries and Related CMake Options

KokkosKernels_NO_DEFAULT_CUDA_TPLS: BOOL
- Whether CUDA TPLs should be enabled by default.
- Default: OFF
KokkosKernels_NO_DEFAULT_ROCM_TPLS: BOOL
ARMPL
- CMake Options
  - KokkosKernels_ENABLE_TPL_ARMPL: BOOL
    - Whether to enable ARMPL
    - Default: OFF
  - ARMPL_LIBRARIES: STRING
    - the name of the armpl library files to look for (possibly combined with above)
  - ARMPL_LIBRARY_DIRS: STRING
    - which directories to look for armpl/armpl_mp (optionally combined with below)
- Environment Variables
  - under construction...
BLAS
- CMake Options
  - KokkosKernels_ENABLE_TPL_BLAS: BOOL
    - Whether to enable BLAS
    - Default: OFF
  - BLAS_LIBRARIES: STRING
    - Optional override for the libraries that comprise TPL BLAS.
    - Default: None. Default common library names will be searched
  - BLAS_LIBRARY_DIRS: STRING
    - Optional override for the library directories that comprise TPL BLAS.
    - Default: None. Default common library locations will be searched
- Environment Variables
  - under construction...
CBLAS
- CMake Options
  - KokkosKernels_ENABLE_TPL_CBLAS: BOOL
    - Whether to enable CBLAS
    - Default: OFF
  - CBLAS_ROOT
  - CBLAS_LIBRARIES
  - CBLAS_LIBRARY_DIRS
  - CBLAS_INCLUDE_DIRS
- Environment Variables
  - under construction...
CHOLMOD
- CMake Options
  - KokkosKernels_ENABLE_TPL_CHOLMOD: BOOL
    - Whether to enable CHOLMOD
    - Default: OFF
  - CHOLMOD_ROOT
  - CHOLMOD_LIBRARIES
  - CHOLMOD_LIBRARY_DIRS
  - CHOLMOD_INCLUDE_DIRS
- Environment Variables
  - under construction...
CUBLAS
- CMake Options
  - KokkosKernels_ENABLE_TPL_CUBLAS: BOOL
    - Whether to enable CUBLAS
    - Default: ON if CUDA-enabled Kokkos, otherwise OFF
  - TPLCUBLAS_ROOT
    - As a side-effect of find_library being called from within find_package(CUDA) which we use to find the CUDA libraries
- Environment Variables
  - under construction...
CUSOLVER
- CMake Options
  - KokkosKernels_ENABLE_TPL_CUSOLVER: BOOL
    - Whether to enable CUSOLVER
    - Default: ON if CUDA-enabled Kokkos, otherwise OFF
  - TPLCUSOLVER_ROOT
    - As a side-effect of find_library being called from within find_package(CUDA) which we use to find the CUDA libraries
- Environment Variables
  - under construction...
CUSPARSE
- CMake Options
  - KokkosKernels_ENABLE_TPL_CUSPARSE: BOOL
    - Whether to enable CUSPARSE
    - Default: ON if CUDA-enabled Kokkos, otherwise OFF
  - `TPLCUSOLVER_ROOT: STRING
    - Optional override for the library directories that comprise TPL CUSPARSE.
- Environment Variables
  - under construction...
MAGMA
- CMake Options
  - KokkosKernels_ENABLE_TPL_MAGMA: BOOL
    - Whether to enable MAGMA
    - Default: OFF
  - KokkosKernels_MAGMA_ROOT: PATH
    - Location of MAGMA install root.
    - Default: None or the value of the environment variable MAGMA_ROOT if set
- Environment Variables
  - under construction...
MKL
- supported versions:
- CMake Options
  - KokkosKernels_ENABLE_TPL_MKL: BOOL
    - Whether to enable MKL
    - Default: OFF
  - MKL_LIBRARIES: STRING
    - Optional override for the libraries that comprise TPL MKL.
    - Default: None. Default common library names will be searched
  - MKL_LIBRARY_DIRS: STRING
    - Optional override for the library directories that comprise TPL MKL.
    - Default: None. Default common library locations will be searched
  - KokkosKernels_MKL_ROOT: PATH
    - Location of MKL install root.
    - Default: None or the value of the environment variable MKL_ROOT if set
- Environment Variables
  - under construction...
LAPACK
- CMake Options
  - KokkosKernels_ENABLE_TPL_LAPACK: BOOL
    - Whether to enable LAPACK
    - Default: ON if BLAS is enabled, otherwise OFF
  - LAPACK_LIBRARIES: STRING
    - Optional override for the libraries that comprise TPL LAPACK.
    - Default: None. Default common library names will be searched
  - LAPACK_LIBRARY_DIRS: STRING
    - Optional override for the library directories that comprise TPL LAPACK.
    - Default: None. Default common library locations will be searched
  - KokkosKernels_LAPACK_ROOT: PATH
    - Location of LAPACK install root.
    - Default: None or the value of the environment variable LAPACK_ROOT if set
- Environment Variables
  - under construction...
LAPACKE
- CMake Options
  - under construction...
- Environment Variables
  - under construction...
METIS
- CMake Options
  - under construction...
- Environment Variables
  - under construction...
ROCBLAS
- CMake Options
  - under construction...
- Environment Variables
  - under construction...
ROCSOLVER
- CMake Options
  - under construction...
- Environment Variables
  - under construction...
ROCSPARSE
- CMake Options
  - under construction...
- Environment Variables
  - under construction...
SUPERLU
- CMake Options
  - under construction...
- Environment Variables
  - under construction...

Other Options

KokkosKernels_ENABLE_EXPERIMENTAL: BOOL
- Enable building and installation of experimental KokkosKernels features.
- Default: OFF
KokkosKernels_LINALG_OPT_LEVEL: BOOL
- Optimization level for KokkosKernels computational kernels: a nonnegative integer. Higher levels result in better performance that is more uniform for corner cases, but increase build time and library size. The default value is 1, which should give performance within ten percent of optimal on most platforms, for most problems.
- Default: 1
KokkosKernels_ENABLE_SUPERNODAL_SPTRSV: BOOL
- Whether to build supernodal SPTRSV support
- Default: ON