xref: /petsc/src/mat/tests/ex33.c (revision a336c15037c72f93cd561f5a5e11e93175f2efd9)
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";
3 
4 /*
5 Example:
6   mpiexec -n <np> ./ex33 -mem_view -matproduct_batch_size <Bbn>
7 */
8 
9 #include <petsc.h>
10 
11 PetscErrorCode Print_memory(PetscLogDouble mem)
12 {
13   double max_mem, min_mem;
14 
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 }
23 
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];
35 
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));
40 
41   if (rank == 0) {
42     /* proc[0] sends 2 rows to proc[1] */
43     for (i = 0; i < 24; i++) buffer[i] = (PetscScalar)i;
44 
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));
52 
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     for (i = 0; i < 24; i++) buffer[i] = 0.0;
56 
57     disp[0] = 1;
58     PetscCallMPI(MPI_Type_create_indexed_block(1, 2, (const PetscMPIInt *)disp, MPIU_SCALAR, &rtype1));
59     PetscCallMPI(MPI_Type_create_resized(rtype1, 0, 4 * sizeof(PetscScalar), &rtype2));
60 
61     PetscCallMPI(MPI_Type_commit(&rtype2));
62     PetscCallMPI(MPI_Recv(buffer, 6, rtype2, 0, 123, MPI_COMM_WORLD, &status));
63     for (i = 0; i < 4; i++) {
64       for (j = 0; j < 6; j++) PetscCall(PetscPrintf(MPI_COMM_SELF, "  %g", (double)PetscRealPart(buffer[i + j * 4])));
65       PetscCall(PetscPrintf(MPI_COMM_SELF, "\n"));
66     }
67   }
68 
69   if (rank == 0) {
70     PetscCallMPI(MPI_Type_free(&type1));
71     PetscCallMPI(MPI_Type_free(&type2));
72   } else if (rank == 1) {
73     PetscCallMPI(MPI_Type_free(&rtype1));
74     PetscCallMPI(MPI_Type_free(&rtype2));
75   }
76   PetscCallMPI(MPI_Barrier(MPI_COMM_WORLD));
77   PetscFunctionReturn(PETSC_SUCCESS);
78 }
79 
80 int main(int argc, char **args)
81 {
82   PetscInt mA = 2700, nX = 80, nz = 40;
83   /* PetscInt        mA=6,nX=5,nz=2; //small test */
84   PetscLogDouble mem;
85   Mat            A, X, Y;
86   PetscBool      flg = PETSC_FALSE;
87 
88   PetscFunctionBeginUser;
89   PetscCall(PetscInitialize(&argc, &args, NULL, help));
90   PetscCall(PetscOptionsGetBool(NULL, NULL, "-test_mpiderivedtype", &flg, NULL));
91   if (flg) {
92     PetscCall(TestMPIDerivedDataType());
93     PetscCall(PetscFinalize());
94     return 0;
95   }
96 
97   PetscCall(PetscOptionsGetBool(NULL, NULL, "-mem_view", &flg, NULL));
98   PetscCall(PetscMemoryGetCurrentUsage(&mem));
99   if (flg) {
100     PetscCall(PetscPrintf(MPI_COMM_WORLD, "Before start,"));
101     PetscCall(Print_memory(mem));
102   }
103 
104   PetscCall(MatCreateAIJ(PETSC_COMM_WORLD, PETSC_DECIDE, PETSC_DECIDE, mA, mA, nz, NULL, nz, NULL, &A));
105   PetscCall(MatSetRandom(A, NULL));
106   PetscCall(PetscMemoryGetCurrentUsage(&mem));
107   if (flg) {
108     PetscCall(PetscPrintf(MPI_COMM_WORLD, "After creating A,"));
109     PetscCall(Print_memory(mem));
110   }
111 
112   PetscCall(MatCreateDense(PETSC_COMM_WORLD, PETSC_DECIDE, PETSC_DECIDE, mA, nX, NULL, &X));
113   PetscCall(MatSetRandom(X, NULL));
114   PetscCall(PetscMemoryGetCurrentUsage(&mem));
115   if (flg) {
116     PetscCall(PetscPrintf(MPI_COMM_WORLD, "After creating X,"));
117     PetscCall(Print_memory(mem));
118   }
119 
120   PetscCall(MatMatMult(A, X, MAT_INITIAL_MATRIX, PETSC_DETERMINE, &Y));
121   PetscCall(PetscMemoryGetCurrentUsage(&mem));
122   if (flg) {
123     PetscCall(PetscPrintf(MPI_COMM_WORLD, "After MatMatMult,"));
124     PetscCall(Print_memory(mem));
125   }
126 
127   /* Test reuse */
128   PetscCall(MatMatMult(A, X, MAT_REUSE_MATRIX, PETSC_DETERMINE, &Y));
129   PetscCall(PetscMemoryGetCurrentUsage(&mem));
130   if (flg) {
131     PetscCall(PetscPrintf(MPI_COMM_WORLD, "After reuse MatMatMult,"));
132     PetscCall(Print_memory(mem));
133   }
134 
135   /* Check accuracy */
136   PetscCall(MatMatMultEqual(A, X, Y, 10, &flg));
137   PetscCheck(flg, PETSC_COMM_SELF, PETSC_ERR_ARG_NOTSAMETYPE, "Error in MatMatMult()");
138 
139   PetscCall(MatDestroy(&A));
140   PetscCall(MatDestroy(&X));
141   PetscCall(MatDestroy(&Y));
142 
143   PetscCall(PetscFinalize());
144   return 0;
145 }
146 
147 /*TEST
148 
149    test:
150       suffix: 1
151       nsize: 4
152       output_file: output/empty.out
153 
154    test:
155       suffix: 2
156       nsize: 8
157       output_file: output/empty.out
158 
159    test:
160       suffix: 3
161       nsize: 2
162       args: -test_mpiderivedtype
163       output_file: output/ex33_3.out
164 
165 TEST*/
166