Actual source code: ex33.c

  1: static char help[] = "Test memory scalability of MatMatMult() for AIJ and DENSE matrices. \n\
  2: Modified from the code contributed by Ian Lin <iancclin@umich.edu> \n\n";

  4: /*
  5: Example:
  6:   mpiexec -n <np> ./ex33 -mem_view -matmatmult_Bbn <Bbn>
  7: */

  9: #include <petsc.h>

 11: PetscErrorCode Print_memory(PetscLogDouble mem)
 12: {
 13:   double max_mem, min_mem;

 15:   PetscFunctionBeginUser;
 16:   PetscCallMPI(MPI_Reduce(&mem, &max_mem, 1, MPI_DOUBLE, MPI_MAX, 0, MPI_COMM_WORLD));
 17:   PetscCallMPI(MPI_Reduce(&mem, &min_mem, 1, MPI_DOUBLE, MPI_MIN, 0, MPI_COMM_WORLD));
 18:   max_mem = max_mem / 1024.0 / 1024.0;
 19:   min_mem = min_mem / 1024.0 / 1024.0;
 20:   PetscCall(PetscPrintf(MPI_COMM_WORLD, " max and min memory across all processors %.4f Mb, %.4f Mb.\n", (double)max_mem, (double)min_mem));
 21:   PetscFunctionReturn(PETSC_SUCCESS);
 22: }

 24: /*
 25:    Illustrate how to use MPI derived data types.
 26:    It would save memory significantly. See MatMPIDenseScatter()
 27: */
 28: PetscErrorCode TestMPIDerivedDataType()
 29: {
 30:   MPI_Datatype type1, type2, rtype1, rtype2;
 31:   PetscInt     i, j;
 32:   PetscScalar  buffer[24]; /* An array of 4 rows, 6 cols */
 33:   MPI_Status   status;
 34:   PetscMPIInt  rank, size, disp[2];

 36:   PetscFunctionBeginUser;
 37:   PetscCallMPI(MPI_Comm_size(MPI_COMM_WORLD, &size));
 38:   PetscCheck(size >= 2, PETSC_COMM_SELF, PETSC_ERR_WRONG_MPI_SIZE, "Must use at least 2 processors");
 39:   PetscCallMPI(MPI_Comm_rank(MPI_COMM_WORLD, &rank));

 41:   if (rank == 0) {
 42:     /* proc[0] sends 2 rows to proc[1] */
 43:     for (i = 0; i < 24; i++) buffer[i] = (PetscScalar)i;

 45:     disp[0] = 0;
 46:     disp[1] = 2;
 47:     PetscCallMPI(MPI_Type_create_indexed_block(2, 1, (const PetscMPIInt *)disp, MPIU_SCALAR, &type1));
 48:     /* one column has 4 entries */
 49:     PetscCallMPI(MPI_Type_create_resized(type1, 0, 4 * sizeof(PetscScalar), &type2));
 50:     PetscCallMPI(MPI_Type_commit(&type2));
 51:     PetscCallMPI(MPI_Send(buffer, 6, type2, 1, 123, MPI_COMM_WORLD));

 53:   } else if (rank == 1) {
 54:     /* proc[1] receives 2 rows from proc[0], and put them into contiguous rows, starting at the row 1 (disp[0]) */
 55:     PetscInt blen = 2;
 56:     for (i = 0; i < 24; i++) buffer[i] = 0.0;

 58:     disp[0] = 1;
 59:     PetscCallMPI(MPI_Type_create_indexed_block(1, blen, (const PetscMPIInt *)disp, MPIU_SCALAR, &rtype1));
 60:     PetscCallMPI(MPI_Type_create_resized(rtype1, 0, 4 * sizeof(PetscScalar), &rtype2));

 62:     PetscCallMPI(MPI_Type_commit(&rtype2));
 63:     PetscCallMPI(MPI_Recv(buffer, 6, rtype2, 0, 123, MPI_COMM_WORLD, &status));
 64:     for (i = 0; i < 4; i++) {
 65:       for (j = 0; j < 6; j++) PetscCall(PetscPrintf(MPI_COMM_SELF, "  %g", (double)PetscRealPart(buffer[i + j * 4])));
 66:       PetscCall(PetscPrintf(MPI_COMM_SELF, "\n"));
 67:     }
 68:   }

 70:   if (rank == 0) {
 71:     PetscCallMPI(MPI_Type_free(&type1));
 72:     PetscCallMPI(MPI_Type_free(&type2));
 73:   } else if (rank == 1) {
 74:     PetscCallMPI(MPI_Type_free(&rtype1));
 75:     PetscCallMPI(MPI_Type_free(&rtype2));
 76:   }
 77:   PetscCallMPI(MPI_Barrier(MPI_COMM_WORLD));
 78:   PetscFunctionReturn(PETSC_SUCCESS);
 79: }

 81: int main(int argc, char **args)
 82: {
 83:   PetscInt mA = 2700, nX = 80, nz = 40;
 84:   /* PetscInt        mA=6,nX=5,nz=2; //small test */
 85:   PetscLogDouble mem;
 86:   Mat            A, X, Y;
 87:   PetscBool      flg = PETSC_FALSE;

 89:   PetscFunctionBeginUser;
 90:   PetscCall(PetscInitialize(&argc, &args, (char *)0, help));
 91:   PetscCall(PetscOptionsGetBool(NULL, NULL, "-test_mpiderivedtype", &flg, NULL));
 92:   if (flg) {
 93:     PetscCall(TestMPIDerivedDataType());
 94:     PetscCall(PetscFinalize());
 95:     return 0;
 96:   }

 98:   PetscCall(PetscOptionsGetBool(NULL, NULL, "-mem_view", &flg, NULL));
 99:   PetscCall(PetscMemoryGetCurrentUsage(&mem));
100:   if (flg) {
101:     PetscCall(PetscPrintf(MPI_COMM_WORLD, "Before start,"));
102:     PetscCall(Print_memory(mem));
103:   }

105:   PetscCall(MatCreateAIJ(PETSC_COMM_WORLD, PETSC_DECIDE, PETSC_DECIDE, mA, mA, nz, NULL, nz, NULL, &A));
106:   PetscCall(MatSetRandom(A, NULL));
107:   PetscCall(PetscMemoryGetCurrentUsage(&mem));
108:   if (flg) {
109:     PetscCall(PetscPrintf(MPI_COMM_WORLD, "After creating A,"));
110:     PetscCall(Print_memory(mem));
111:   }

113:   PetscCall(MatCreateDense(PETSC_COMM_WORLD, PETSC_DECIDE, PETSC_DECIDE, mA, nX, NULL, &X));
114:   PetscCall(MatSetRandom(X, NULL));
115:   PetscCall(PetscMemoryGetCurrentUsage(&mem));
116:   if (flg) {
117:     PetscCall(PetscPrintf(MPI_COMM_WORLD, "After creating X,"));
118:     PetscCall(Print_memory(mem));
119:   }

121:   PetscCall(MatMatMult(A, X, MAT_INITIAL_MATRIX, PETSC_DEFAULT, &Y));
122:   PetscCall(PetscMemoryGetCurrentUsage(&mem));
123:   if (flg) {
124:     PetscCall(PetscPrintf(MPI_COMM_WORLD, "After MatMatMult,"));
125:     PetscCall(Print_memory(mem));
126:   }

128:   /* Test reuse */
129:   PetscCall(MatMatMult(A, X, MAT_REUSE_MATRIX, PETSC_DEFAULT, &Y));
130:   PetscCall(PetscMemoryGetCurrentUsage(&mem));
131:   if (flg) {
132:     PetscCall(PetscPrintf(MPI_COMM_WORLD, "After reuse MatMatMult,"));
133:     PetscCall(Print_memory(mem));
134:   }

136:   /* Check accuracy */
137:   PetscCall(MatMatMultEqual(A, X, Y, 10, &flg));
138:   PetscCheck(flg, PETSC_COMM_SELF, PETSC_ERR_ARG_NOTSAMETYPE, "Error in MatMatMult()");

140:   PetscCall(MatDestroy(&A));
141:   PetscCall(MatDestroy(&X));
142:   PetscCall(MatDestroy(&Y));

144:   PetscCall(PetscFinalize());
145:   return 0;
146: }

148: /*TEST

150:    test:
151:       suffix: 1
152:       nsize: 4
153:       output_file: output/ex33.out

155:    test:
156:       suffix: 2
157:       nsize: 8
158:       output_file: output/ex33.out

160:    test:
161:       suffix: 3
162:       nsize: 2
163:       args: -test_mpiderivedtype
164:       output_file: output/ex33_3.out

166: TEST*/