Am Di., 1. Feb. 2022 um 16:20 Uhr schrieb Jed Brown <j...@jedbrown.org>:
> Patrick Sanan <patrick.sa...@gmail.com> writes: > > > Sorry about the delay on this. I can reproduce. > > > > This regression appears to be a result of this optimization: > > https://gitlab.com/petsc/petsc/-/merge_requests/4273 > > Thanks for tracking this down. Is there a reason to prefer preallocating > twice > > ierr = > MatPreallocatorPreallocate(preallocator,PETSC_TRUE,A);CHKERRQ(ierr); > ierr = > MatPreallocatorPreallocate(preallocator,PETSC_TRUE,A_duplicate);CHKERRQ(ierr); > > versus using MatDuplicate() or MatConvert()? > Maybe if your preallocation is an overestimate for each of two different post-assembly non-zero structures in A and A_duplicate?
