suffix off suffix on suffix gpu
This command allows you to use variants of various styles if they exist. In that respect it operates the same as the -suffix command-line switch. It also has options to turn off/on any suffix setting made via the command line.
The specified style can be opt, omp, gpu, or cuda. These refer to optional packages that LAMMPS can be built with, as described in this section of the manual. The "opt" style corrsponds to the OPT package, the "omp" style to the USER-OMP package, the "gpu" style to the GPU package, and the "cuda" style to the USER-CUDA package.
These are the variants these packages provide:
As an example, all of the packages provide a pair_style lj/cut variant, with style names lj/cut/opt, lj/cut/omp, lj/cut/gpu, or lj/cut/cuda. A variant styles can be specified explicitly in your input script, e.g. pair_style lj/cut/gpu. If the suffix command is used with the appropriate style, you do not need to modify your input script. The specified suffix (opt,omp,gpu,cuda) is automatically appended whenever your input script command creates a new atom, pair, bond, angle, dihedral, improper, kspace, fix, compute, or run style. If the variant version does not exist, the standard version is created.
If the specified style is off, then any previously specified suffix is temporarily disabled, whether it was specified by a command-line switch or a previous suffix command. If the specified style is on, a disabled suffix is turned back on. The use of these 2 commands lets your input script use a standard LAMMPS style (i.e. a non-accelerated variant), which can be useful for testing or benchmarking purposes. Of course this is also possible by not using any suffix commands, and explictly appending or not appending the suffix to the relevant commands in your input script.
Command-line switch -suffix