Running Enzo with CUDA¶
Enzo contains a CUDA MHD solver. Supported parameters include
- Riemann Solver: HLL-PLM
- Color fields: chemistry, etc
- Driving field
- Comoving coordinates
How to compile with CUDA¶
In order to make Enzo compatible with CUDA, a few changes need to be made in the settings.
The first thing is to locate the Makefiles located within the src/ directory in the Enzo repository. Make sure then that CONFIG_ECUDA=yes
Then locate your machine specific Makefile, e.g. Make.mach.mymach, and then set the following variables:
MACH_OPT_CUDA = -arch=sm_20 -03 MACH_LIBS_CUDA = -L/your/cuda/install/dir/lib64 -lcudart
If using the Kepler K20 GPU, then
MACH_OPT_CUDA = -arch=sm_35 -03
Last thing to note is that the CUDA solver is single precision only. Check to make sure that all the precision flags are set correctly. For example,
MACH_FFLAGS_INTEGER_32 = MACH_FFLAGS_INTEGER_64 = -i8 MACH_FFLAGS_REAL_32 = MACH_FFLAGS_REAL_64 = -r8
How to run with CUDA¶
The only thing to do is to set UseCUDA=1 in whichever parameter file. That’s all!
Be sure that each node has at least 1 NVIDIA GPU. Also note that although each GPU can be running multiple MPI processes, the performance will not increase beyond 1 MPI process per GPU.