PETSc is a scalable package for solving differential and algebraic equations. It supports MPI, and GPUs through CUDA or OpenCL, as well as hybrid MPI-GPU parallelism.
As part of CEED, the PETSc project will coordinate the development of expressive interfaces for efficient and robust solution of the algebraic equations appearing in high-order/spectral element methods. This will include multilevel solvers that work with unassembled representations of linear operators.
PETSc is freely available under a BSD license.
In CEED, PETSc is primarily involved in the efforts of the Software thrust.
For more information, see the PETSc website: https://www.mcs.anl.gov/petsc/.