Dear Bruno, thank you very much. I am having some troubles to install the new version with CUDA and MPI using 'nvcc_wrapper', but, once solved these issues (hopefully), I will definitely try with the last version of deal.II.
Best, Giuseppe Il giorno lunedì 17 luglio 2023 alle 20:34:18 UTC+2 [email protected] ha scritto: > Giuseppe, > > We totally rewrote the GPU matrix-free framework on the latest release of > deal.II (version 9.5). One of the advantages is that you can now > write/debug the code on the CPU and then switch to run the code on the GPU. > The new code is not 100% backward compatible but the changes are pretty > small. I advise you to switch to the latest version of deal.II, debug the > code on the CPU, and then run on the GPU. > > Best, > > Bruno > > Le lun. 17 juil. 2023 à 14:12, giuseppe orlando <[email protected]> a > écrit : > >> Dear Bruno, >> thank you very much. That was the issue with the matrix-based version. >> I take the opportunity for another question (sorry in advance to bother). >> I also tried to implement a matrix-free version of the same problem, >> exploiting therefore all the routines such as 'assemble_rhs' and delegating >> the action of the matrix to suitable operators. The results are the same >> for a few time-steps and then it blows up. I guess that it is something >> again related to the memory access, but I couldn't figure out the issue. In >> thics case, it should not be CUDA::Handle, because I am not using it since >> we are in a matrix-free framework. >> >> Thanks again for the previous suggestion. >> >> Best, >> >> Giuseppe >> >> Il giorno lunedì 17 luglio 2023 alle 17:50:27 UTC+2 [email protected] >> ha scritto: >> >>> Giuseppe, >>> >>> The CUDA::Handle needs to live longer than the sparse matrix but in your >>> code it goes out-of-scope at the end of assemble_system(). I know the same >>> code works with assemble_matrix but it only works "by chance" because >>> nothing wrote over the memory. I don't know if that's the only problem but >>> that's definitely wrong. >>> >>> Best, >>> >>> Bruno >>> >>> Le lun. 17 juil. 2023 à 11:06, giuseppe orlando <[email protected]> a >>> écrit : >>> >>>> Here, you can find the two codes. 'SBR_GPU' is the one that arrives up >>>> to the end, whereas 'SBR_GPU_WRONG' is the one that stops with the error >>>> described above once I call 'output_results'. If the code is too long and >>>> can be helpful, I could try to reduce it avoiding ParameterHandler and >>>> other more 'advanced' stuff and to reduce everything to a unique file. >>>> >>>> Best, >>>> >>>> Giuseppe >>>> >>>> Il giorno lunedì 17 luglio 2023 alle 16:11:18 UTC+2 >>>> [email protected] ha scritto: >>>> >>>>> Giuseppe, >>>>> >>>>> It's hard to tell what's wrong without seeing the code. >>>>> >>>>> Best, >>>>> >>>>> Bruno >>>>> >>>>> On Monday, July 17, 2023 at 9:04:42 AM UTC-4 [email protected] wrote: >>>>> >>>>>> Hello everyone, >>>>>> I'm writing this post to ask some help for a CUDA code. I have >>>>>> implemented a matrix-based CUDA coda for the so-called solid body >>>>>> rotation, >>>>>> namely a time dependent advection problem. In my first implementation, I >>>>>> encapulased the computation of the matrix and of the right-hand side of >>>>>> the >>>>>> resulting linear system in the same routine ('assemble_system'). Then, I >>>>>> tried to separate the assembling of the matrix ('assemble_matrix') and >>>>>> of >>>>>> the rhs ('assemble_rhs'). Since the matrix does not change (I am using >>>>>> an >>>>>> explicit time integration scheme and, therefore, the resulting matrix is >>>>>> a >>>>>> mass matrix), I compute it at the beginning and then I just update the >>>>>> right-hand side. Everything works until I save the results, after which >>>>>> I >>>>>> obtain this error ("On entry to cusparseSpMV() parameter number 1 >>>>>> (handle) >>>>>> had an illegal value: invalid pointer mode"). >>>>>> I also tried to create an auxiliary vector just for saving, but >>>>>> nothing changes. >>>>>> Everything runs with 1 GPU. Have anyone ever obtained this kind of >>>>>> issue? If it can help, I can share the two versions of the code. >>>>>> >>>>>> Thanks in advance >>>>>> >>>>>> Best >>>>>> >>>>>> Giuseppe >>>>>> >>>>> -- >>>> The deal.II project is located at http://www.dealii.org/ >>>> For mailing list/forum options, see >>>> https://groups.google.com/d/forum/dealii?hl=en >>>> --- >>>> You received this message because you are subscribed to a topic in the >>>> Google Groups "deal.II User Group" group. >>>> To unsubscribe from this topic, visit >>>> https://groups.google.com/d/topic/dealii/p5eZs3NaGRk/unsubscribe. >>>> To unsubscribe from this group and all its topics, send an email to >>>> [email protected]. >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/dealii/9d079799-6b51-46f6-8564-8058877e83d7n%40googlegroups.com >>>> >>>> <https://groups.google.com/d/msgid/dealii/9d079799-6b51-46f6-8564-8058877e83d7n%40googlegroups.com?utm_medium=email&utm_source=footer> >>>> . >>>> >>> -- >> The deal.II project is located at http://www.dealii.org/ >> For mailing list/forum options, see >> https://groups.google.com/d/forum/dealii?hl=en >> --- >> You received this message because you are subscribed to a topic in the >> Google Groups "deal.II User Group" group. >> To unsubscribe from this topic, visit >> https://groups.google.com/d/topic/dealii/p5eZs3NaGRk/unsubscribe. >> To unsubscribe from this group and all its topics, send an email to >> [email protected]. >> > To view this discussion on the web visit >> https://groups.google.com/d/msgid/dealii/7f8102ef-3bce-4e15-b1ae-d18c0ca7e2fbn%40googlegroups.com >> >> <https://groups.google.com/d/msgid/dealii/7f8102ef-3bce-4e15-b1ae-d18c0ca7e2fbn%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. 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