Work on faster petsc assembling.

AMDiS/src/ParallelDomainBase.cc

@@ -306,14 +306,11 @@ namespace AMDiS {
 
     clock_t first = clock();
 
-    //    MatCreate(PETSC_COMM_WORLD, &petscMatrix);
-    //    MatSetSizes(petscMatrix, nRankRows, nRankRows, nOverallRows, nOverallRows);
-    //MatSetType(petscMatrix, MATAIJ);
-
     using mtl::tag::major; using mtl::tag::nz; using mtl::begin; using mtl::end;
     namespace traits= mtl::traits;
     typedef DOFMatrix::base_matrix_type Matrix;
 
+    int nnz = 0;
     int d_nnz[nRankRows];
     for (int i = 0; i < nRankRows; i++)
       d_nnz[i] = 0;
@@ -344,10 +341,12 @@ namespace AMDiS {
 	  }
 	}
 
-    INFO(info, 8)("t1 petsc matrix needed %.5f seconds\n", TIME_USED(first, clock()));
+    for (int i = 0; i < nRankRows; i++)
+      if (d_nnz[i] > nnz)
+	nnz = d_nnz[i];
 
     MatCreateMPIAIJ(PETSC_COMM_WORLD, nRankRows, nRankRows, nOverallRows, nOverallRows,
-		    0, d_nnz, 0, NULL, &petscMatrix);
+		    nnz, NULL, nnz / 10, NULL, &petscMatrix);
 
     using mtl::tag::major; using mtl::tag::nz; using mtl::begin; using mtl::end;
     namespace traits= mtl::traits;
@@ -453,7 +452,7 @@ namespace AMDiS {
     KSPSetOperators(ksp, petscMatrix, petscMatrix, DIFFERENT_NONZERO_PATTERN);
     KSPGetPC(ksp, &pc);
     //    PCSetType(pc, PCNONE);
-    PCSetType(pc, PCJACOBI);
+    PCSetType(pc, PCSOR);
     KSPSetTolerances(ksp, 1.e-7, PETSC_DEFAULT, PETSC_DEFAULT, PETSC_DEFAULT);
     KSPSetType(ksp, KSPBCGS);
     //KSPSetType(ksp, KSPCG);