Added save K and M

Solver/linearSystemPETSc.hpp

@@ -103,7 +103,7 @@ void linearSystemPETSc<scalar>::preAllocateEntries()
   int blockSize = _getBlockSizeFromParameters();
   std::vector<int> nByRowDiag (_localSize), nByRowOffDiag (_localSize);
   if (_sparsity.getNbRows() == 0) {
-    PetscInt prealloc = 300;
+    PetscInt prealloc = 500;
     PetscBool set;
     PetscOptionsGetInt(PETSC_NULL, "-petsc_prealloc", &prealloc, &set);
     prealloc = std::min(prealloc, _localSize);