This speeds up the matrix vector products in the IterativeSchurSolver by upto 40%. Change-Id: Ib5e8d77c7269cf5ffdd2d161893734bb6d38215d
Change-Id: I13b2b951297ae81bfab0a7b4991a791ed91d594c
unnecessarily complexity in the structure of linear solvers and preconditioners. This is the first step towards cleaning up the Preconditioner interface. 2. Minor tweaks and cleanups to the various linear solvers.