xref: /petsc/src/mat/tests/ex33.c (revision daa037dfd3c3bec8dc8659548d2b20b07c1dc6de)
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 -matmatmult_Bbn <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(0);
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;  disp[1] = 2;
46     PetscCallMPI(MPI_Type_create_indexed_block(2, 1, (const PetscMPIInt *)disp, MPIU_SCALAR, &type1));
47     /* one column has 4 entries */
48     PetscCallMPI(MPI_Type_create_resized(type1,0,4*sizeof(PetscScalar),&type2));
49     PetscCallMPI(MPI_Type_commit(&type2));
50     PetscCallMPI(MPI_Send(buffer, 6, type2, 1, 123, MPI_COMM_WORLD));
51 
52   } else if (rank == 1) {
53     /* proc[1] receives 2 rows from proc[0], and put them into contiguous rows, starting at the row 1 (disp[0]) */
54     PetscInt blen = 2;
55     for (i=0; i<24; i++) buffer[i] = 0.0;
56 
57     disp[0] = 1;
58     PetscCallMPI(MPI_Type_create_indexed_block(1, blen, (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++) {
65         PetscCall(PetscPrintf(MPI_COMM_SELF,"  %g", (double)PetscRealPart(buffer[i+j*4])));
66       }
67       PetscCall(PetscPrintf(MPI_COMM_SELF,"\n"));
68     }
69   }
70 
71   if (rank == 0) {
72     PetscCallMPI(MPI_Type_free(&type1));
73     PetscCallMPI(MPI_Type_free(&type2));
74   } else if (rank == 1) {
75     PetscCallMPI(MPI_Type_free(&rtype1));
76     PetscCallMPI(MPI_Type_free(&rtype2));
77   }
78   PetscCallMPI(MPI_Barrier(MPI_COMM_WORLD));
79   PetscFunctionReturn(0);
80 }
81 
82 int main(int argc, char **args)
83 {
84   PetscInt          mA = 2700,nX = 80,nz = 40;
85   /* PetscInt        mA=6,nX=5,nz=2; //small test */
86   PetscLogDouble    mem;
87   Mat               A,X,Y;
88   PetscBool         flg = PETSC_FALSE;
89 
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   }
97 
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   }
104 
105   PetscCall(MatCreateAIJ(PETSC_COMM_WORLD,PETSC_DECIDE,PETSC_DECIDE,mA,mA,nz,PETSC_NULL,nz,PETSC_NULL,&A));
106   PetscCall(MatSetRandom(A,PETSC_NULL));
107   PetscCall(PetscMemoryGetCurrentUsage(&mem));
108   if (flg) {
109     PetscCall(PetscPrintf(MPI_COMM_WORLD, "After creating A,"));
110     PetscCall(Print_memory(mem));
111   }
112 
113   PetscCall(MatCreateDense(PETSC_COMM_WORLD,PETSC_DECIDE,PETSC_DECIDE,mA,nX,PETSC_NULL,&X));
114   PetscCall(MatSetRandom(X,PETSC_NULL));
115   PetscCall(PetscMemoryGetCurrentUsage(&mem));
116   if (flg) {
117     PetscCall(PetscPrintf(MPI_COMM_WORLD, "After creating X,"));
118     PetscCall(Print_memory(mem));
119   }
120 
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   }
127 
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   }
135 
136   /* Check accuracy */
137   PetscCall(MatMatMultEqual(A,X,Y,10,&flg));
138   PetscCheck(flg,PETSC_COMM_SELF,PETSC_ERR_ARG_NOTSAMETYPE,"Error in MatMatMult()");
139 
140   PetscCall(MatDestroy(&A));
141   PetscCall(MatDestroy(&X));
142   PetscCall(MatDestroy(&Y));
143 
144   PetscCall(PetscFinalize());
145   return 0;
146 }
147 
148 /*TEST
149 
150    test:
151       suffix: 1
152       nsize: 4
153       output_file: output/ex33.out
154 
155    test:
156       suffix: 2
157       nsize: 8
158       output_file: output/ex33.out
159 
160    test:
161       suffix: 3
162       nsize: 2
163       args: -test_mpiderivedtype
164       output_file: output/ex33_3.out
165 
166 TEST*/
167