# 3.2. Build LAMMPS with make

Building LAMMPS with traditional makefiles requires that you have a Makefile.”machine” file appropriate for your system in the src/MAKE, src/MAKE/MACHINES, src/MAKE/OPTIONS, or src/MAKE/MINE directory (see below). It can include various options for customizing your LAMMPS build with a number of global compilation options and features.

To include LAMMPS packages (i.e. optional commands and styles) you must install them first, as discussed on the Build package doc page. If the packages require provided or external libraries, you must build those libraries before building LAMMPS. Building LAMMPS with CMake can automate all of this for many types of machines, especially workstations, desktops and laptops, so we suggest you try it first.

These commands perform a default LAMMPS build, producing the LAMMPS executable lmp_serial or lmp_mpi in lammps/src:

cd lammps/src
make serial     # build a serial LAMMPS executable
make mpi        # build a parallel LAMMPS executable with MPI
make            # see a variety of make options


This initial compilation can take a long time, since LAMMPS is a large project with many features. If your machine has multiple CPU cores (most do these days), using a command like “make -jN mpi” (with N = the number of available CPU cores) can be much faster. If you plan to do development on LAMMPS or need to re-compile LAMMPS repeatedly, the installation of the ccache (= Compiler Cache) software may speed up compilation even more.

After the initial build, whenever you edit LAMMPS source files, or add or remove new files to the source directory (e.g. by installing or uninstalling packages), you must re-compile and relink the LAMMPS executable with the same “make” command. This makefiles dependencies should insure that only the subset of files that need to be are re-compiled.

Note

When you build LAMMPS for the first time, a long list of *.d files will be printed out rapidly. This is not an error; it is the Makefile doing its normal creation of dependencies.

The lammps/src/MAKE tree contains all the Makefile.machine files included in the LAMMPS distribution. Typing “make machine” uses Makefile.machine. Thus the “make serial” or “make mpi” lines above use Makefile.serial and Makefile.mpi. Others are in these dirs:

OPTIONS      # Makefiles which enable specific options
MACHINES     # Makefiles for specific machines
MINE         # customized Makefiles you create (you may need to create this folder)


Typing “make” lists all the available Makefile.machine files. A file with the same name can appear in multiple folders (not a good idea). The order the dirs are searched is as follows: src/MAKE/MINE, src/MAKE, src/MAKE/OPTIONS, src/MAKE/MACHINES. This gives preference to a customized file you put in src/MAKE/MINE.

Makefiles you may wish to try include these (some require a package first be installed). Many of these include specific compiler flags for optimized performance. Please note, however, that some of these customized machine Makefile are contributed by users. Since both compilers, OS configurations, and LAMMPS itself keep changing, their settings may become outdated:

make mac             # build serial LAMMPS on a Mac
make mac_mpi         # build parallel LAMMPS on a Mac
make intel_cpu       # build with the USER-INTEL package optimized for CPUs
make knl             # build with the USER-INTEL package optimized for KNLs
make opt             # build with the OPT package optimized for CPUs
make omp             # build with the USER-OMP package optimized for OpenMP
make kokkos_omp      # build with the KOKKOS package for OpenMP
make kokkos_cuda_mpi # build with the KOKKOS package for GPUs
make kokkos_phi      # build with the KOKKOS package for KNLs