MueLu/regionMG: separate setup and apply of coarse solver
Created by: mayrmt
@trilinos/muelu
Description
Split setup and solve of the composite coarse level solver into two parts. Do the setup during hierarchy construction and just apply the solver during the V-cycle.
I also have removed commented and obsolete code from my previous unsuccessful attempts to create a coarse solver.
Motivation and Context
The matrix does not change, it's sufficient to create the solver once and then just re-use multiple times. This should save unecessary setup costs.
Related Issues
- Closes #5072 (closed)
How Has This Been Tested?
Build and regionMG tests pass locally.
Checklist
-
My commit messages mention the appropriate GitHub issue numbers. -
My code follows the code style of the affected package(s). -
My change requires a change to the documentation. -
I have updated the documentation accordingly. -
I have read the code contribution guidelines for this project. -
I have added tests to cover my changes. -
All new and existing tests passed. -
No new compiler warnings were introduced. -
These changes break backwards compatibility.