On Mon, Apr 9, 2018 at 6:12 PM, Manuel Valera <mvaler...@sdsu.edu> wrote:
> Hello guys, > > I've made advances in my CUDA acceleration project, as you remember i have > a CFD model in need of better execution times. > > So far i have been able to solve the pressure system in the GPU and the > rest in serial, using PETSc only for this pressure solve, the library i got > to work was ViennaCL. First question, do i still have to switch > installations to use either CUDA library? this was a suggestion before, so > in order to use CUSP instead of ViennaCL, for example, i currently have to > change installations, is this still the case? > I am not sure what that means exactly. However, you can build a PETSc with CUDA and ViennaCL support. The type of Vec/Mat is selected at runtime. > Now, i started working in a fully parallelized version of the model, which > uses the DMs and DMDAs to distribute the arrays, if i try the same flags as > before i get an error saying "Currently only handles ViennaCL matrices" > when trying to solve for pressure, i get this is a feature still not > implemented? what options do i have to solve pressure, or assign a DMDA > array update to be done specifically in a GPU device? > If we can't see the error, we are just guessing. Please send the entire error message. Note, we only do linear algebra on the GPU, so none of the FormFunction/FormJacobian stuff for DMDA would be on the GPU. > I was thinking of using the VecScatterCreateToZero for a regular vector, > Why do you want a serial vector? > but then i would have to create a vector and copy the DMDAVec into it, > I do not understand what it means to copy the DM into the Vec. Thanks, Matt > is this accomplished with DMDAVecGetArrayReadF90 and then just copy? do > you think this will generate too much overhead? > > Thanks so much for your input, > > Manuel > -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener https://www.cse.buffalo.edu/~knepley/ <http://www.caam.rice.edu/~mk51/>