[petsc-users] question about petsc and gpus

[Barry Smith]

On May 3, 2011, at 12:06 PM, Randall Mackie wrote:

> I have access to a computer with a GPU, and I wanted to play around a bit with petsc on this gpu.
> So I have compiled petsc-dev with cusp, thrust, and cuda to give GPU support, and I am ready
> to run some examples.
> 
> However, something is not clear to me: how does petsc know which gpu to run something on?
> For example, this machine has two gpus: one for the display, and then one compute gpu.
> So I see /dev/nvidia0 and /dev/nvidia1. If I just issue the command from the petsc web page,
> will it run it on the right gpu?
> 
> 
> Also, what if a computer has two compute gpus? Does petsc use both of them or only one?
> 
> 
> Thanks in advance,
> 
> Randy

  Randy,

    This is something we don't know anything about. How to assign GPUs to processes etc. You'll need to read the Nvidia documentation to find out how to do this sort of thing.

   If you figure this out, we'll add it to our documentations.

    Barry