Re: [ESPResSo-devel] Porting Interaction Calculations to CUDA

[Axel Arnold]

Hi!

If I didn't missunderstand you, you basically want to do the same as the LB-
GPU code. That code also copies the positions and velocities to the GPU and 
gets the forces back. The interesting parts for you are lbgpu_cfile.c,  
lb_calc_particle_lattice_ia_gpu and lb_send_forces_gpu. These also handle the 
gathering of the parallely distributed particle data.

There are some minor issues with the C++/C interfacing since CUDA is 
inherently C++, but that can be solved using "extern "C" {}" constructs. In 
any case, you don't need to recompile the whole code, just your GPU code and 
of course linking.

Axel

On Tuesday 24 April 2012, Toson Peter wrote:
> Hallo!
> 
> I am trying to port the force calculation of some self-implemented
> bonded interactions to CUDA. For a beginning, I would like to write
> isolated tests (for performance and correctness) comparing
> the CPU and GPU calculations.
> 
> The tests should look something like this:
> 
> ================================================================
> build Particles
> build Interactions
> 
> for each Particle P {
>     for each Interaction I of P {
>         add force cause by I to P
>     }
> }
> 
> convert Particle and Interaction data to a GPU-friendly format
> do force calculation on GPU
> 
> compare results and times
> ================================================================
> 
> What would be the best way to do it, without compiling whole ESPResSo
> after any change to the GPU-Implementation?
> 
> 
> "Only" using the Particle and Interaction structs from ESPResSo? Is
> that even possible considering the many includes in particle_data.h/c?
> 
> Implementing fake Particle and Interaction structs containing only the
> members needed for the force calculation?
> 
> Some other way I did not think of?
> 
> 
> --
> Peter Toson
> Industrial Simulation
> St. Poelten University of Applied Sciences


-- 
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