linux

Prerequisites for MUMPS installation on Linux

We need the following tools before compiling MUMPS on Linux.

Compilers

The compilation of MUMPS requires both C and Fortran compilers. Although both C and Fortran compilers are included in GNU Compiler Collection (GCC), we recommend using Intel C compiler, Fortran compiler, and MPI library.

On a Linux cluster, if Intel compilers and MPI library are not loaded, we may load them on a Lmod module system by typing

module load intel
module load intel intel-mpi

In non-Lmod module system, we may type (for Intel oneAPI),

source .../intel/oneapi/compiler/latest/env/vars.sh
source  .../intel/oneapi/mpi/latest/env/vars.sh

where ... is the path to Intel folder.

On a local Linux machine, we can download the Intel installer here. Make sure to use custom installation and choose the following: (a) Intel Inspector (b) Intel MPI Library (c) Intel oneAPI DPC++/C++ Compiler & Intel C++ Compiler Classic (d) Intel Fortran Compiler & Intel Fortran Compiler Classic

After installing the Intel compiler, we need to set the environment variables specific to these compilers. Run the following commands:

source opt/intel/oneapi/compiler/latest/env/vars.sh
source opt/intel/oneapi/mpi/latest/env/vars.sh

These commands will configure the necessary environment variables for the Intel compilers, and Intel MPI.

BLAS, LAPACK, and ScaLAPACK

MUMPS requires both BLAS, LAPACK, and ScaLAPACK libraries, which are standard libraries on a Linux cluster. These libraries are also included in many implementations, such as MKL and OpenBLAS.

In the example below, we use MKL. Different clusters install MKL in different paths. We will need the correct path for the linker to find corresponding BLAS, LAPACK, and ScaLAPACK libraries. In the provided Makefile.inc, we assume the MKL path has been exported to an environment variable called MKLROOT. Here we show how to export the correct MKLROOT. The BLAS, LAPACK, and ScaLAPACK libraries can be found under $(MKLROOT)/lib/intel64.

If we are using the Lmod module system and MKL is installed, we can use

module load intel
module load intel-mkl
echo $MKLROOT

MKLROOT is assigned and should be printed out, if MKL is available. The MKLROOT should be under the path .../mkl, where ... is the Intel directory path.

If Lmod module system is not used in our cluster, then we can also try to find the path like .../intel/oneapi/mkl, where ... is the Intel directory path. Then we can assign the MKLROOT by

source .../mkl/bin/mklvars.sh intel64
echo $MKLROOT

MKLROOT is assigned and should be printed out.

On a local machine, please visit Intel oneAPI Math Kernel Library to install MKL. During the installation process, ensure that we select custom installation and choose only the Intel oneAPI Math Kernel Library. This will ensure the necessary libraries are properly installed for MUMPS to function correctly.

After installing the MKL, we can set the environment variable MKLROOT. Run the following commands:

source /opt/intel/oneapi/mkl/latest/env/vars.sh
echo $MKLROOT

MKLROOT is assigned and should be printed out.

Note that MUMPS supports shared memory, multithreaded parallelism through the use of multithreaded BLAS libraries. We provide Makefile.inc on Linux and they activate the OpenMP feature. We can use the environment variable OMP_NUM_THREADS to set the number of threads.