Petsc supports ILU0/ICC0 numeric factorization (without reordering) and then triangular solve on GPUs. It is done by calling vendor libraries (ex. cusparse). We have options -pc_factor_mat_factor_on_host <bool> -pc_factor_mat_solve_on_host <bool> to force doing the factorization and MatSolve on the host for device matrix types.
You can try to see if it works for your case. --Junchao Zhang On Mon, Apr 14, 2025 at 4:39 PM Angus, Justin Ray via petsc-dev < petsc-dev@mcs.anl.gov> wrote: > Hello, > > > > A project I work on uses GMRES via PETSc. In particular, we have had good > successes using the Additive Schwarz Method + ILU preconditioner setup > using a CPU-based code. I found online where it is stated that “Parts of > most preconditioners run directly on the GPU” ( > https://urldefense.us/v3/__https://petsc.org/release/faq/__;!!G_uCfscf7eWS!eyXTlwwR7hk0RuEHQeXwSjtY-JDprhL8r0c2jgb_kBbJWzN8qkstC-zZhjwPAO_p1MjiVAFFHjIFiA1HWp2uDuxVekdn$ > > <https://urldefense.us/v3/__https://petsc.org/release/faq/__;!!G_uCfscf7eWS!bw6qeKcY7MKSvlEgcogdKR7fpjZSOFvka6zfDprUZ_sJHdE-YZmRD6UTqWQW3_uGVBII4P-AG0zaGTLbI67_fQ$>). > Is ASM + ILU also available for GPU platforms? > > > > -Justin >
