Compute Backends

The following inputs must be preceded by amrex. and determine runtime options of CPU or GPU compute implementations.

Parameter	Description	Type	Default
omp_threads	If OpenMP is enabled, this can be used to set the default number of threads. The special value nosmt can be used to avoid using threads for virtual cores (aka Hyperthreading or SMT), as is default in OpenMP, and instead only spawns threads equal to the number of physical cores in the system. For the values system and nosmt, the environment variable OMP_NUM_THREADS takes precedence. For Integer values, OMP_NUM_THREADS is ignored.	String or Int	system

For GPU-specific parameters, see also the GPU chapter.