Hi all, I am trying to accelerate the linear solver with PETSc GPU backend. For testing I have a simple 1D heat diffusion solver, here are some observations. 1. If I use -pc_type gamg it throws the following error ** On entry to cusparseCreateCsr() parameter number 5 (csrRowOffsets) had an illegal value: NULL pointer
[0]PETSC ERROR: --------------------- Error Message -------------------------------------------------------------- [0]PETSC ERROR: GPU error [0]PETSC ERROR: cuSPARSE errorcode 3 (CUSPARSE_STATUS_INVALID_VALUE) : invalid value [0]PETSC ERROR: See https://petsc.org/release/faq/ for trouble shooting. [0]PETSC ERROR: Petsc Development GIT revision: v3.19.4-959-g92f1e92e88 GIT Date: 2023-08-13 19:43:04 +0000 2. Default pc ilu takes about 1.2 seconds on a single CPU and it takes about 105.9 seconds on a GPU. Similar observations with pc_type asm I have NVIDIA RTX A2000 8GB Laptop GPU 3. What I could be missing? Also, are there any general guidelines for better GPU performance using PETSc? Regards, Maruthi
