xref: /petsc/src/sys/tutorials/ex3.c (revision fbf9dbe564678ed6eff1806adbc4c4f01b9743f4) !
1 
2 static char help[] = "Augmenting PETSc profiling by add events.\n\
3 Run this program with one of the\n\
4 following options to generate logging information:  -log, -log_view,\n\
5 -log_all.  The PETSc routines automatically log event times and flops,\n\
6 so this monitoring is intended solely for users to employ in application\n\
7 codes.\n\n";
8 
9 /*
10   Include "petscsys.h" so that we can use PETSc profiling routines.
11 */
12 #include <petscsys.h>
13 #include <petscviewer.h>
14 
15 int main(int argc, char **argv)
16 {
17   PetscMPIInt   rank;
18   int           i, imax = 10000, icount;
19   PetscLogEvent USER_EVENT, check_USER_EVENT;
20 
21   PetscFunctionBeginUser;
22   PetscCall(PetscInitialize(&argc, &argv, NULL, help));
23 
24   /*
25      Create a new user-defined event.
26       - Note that PetscLogEventRegister() returns to the user a unique
27         integer event number, which should then be used for profiling
28         the event via PetscLogEventBegin() and PetscLogEventEnd().
29       - The user can also optionally log floating point operations
30         with the routine PetscLogFlops().
31   */
32   PetscCall(PetscLogEventRegister("User event", PETSC_VIEWER_CLASSID, &USER_EVENT));
33   PetscCall(PetscLogEventGetId("User event", &check_USER_EVENT));
34   PetscCheck(USER_EVENT == check_USER_EVENT, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Event Ids do not match");
35 
36   PetscCall(PetscLogEventBegin(USER_EVENT, 0, 0, 0, 0));
37   icount = 0;
38   for (i = 0; i < imax; i++) icount++;
39   (void)icount;
40   PetscCall(PetscLogFlops(imax));
41   PetscCall(PetscSleep(0.5));
42   PetscCall(PetscLogEventEnd(USER_EVENT, 0, 0, 0, 0));
43 
44   /*
45      We disable the logging of an event.
46 
47   */
48   PetscCall(PetscLogEventDeactivate(USER_EVENT));
49   PetscCall(PetscLogEventBegin(USER_EVENT, 0, 0, 0, 0));
50   PetscCall(PetscSleep(0.5));
51   PetscCall(PetscLogEventEnd(USER_EVENT, 0, 0, 0, 0));
52 
53   /*
54      We next enable the logging of an event
55   */
56   PetscCall(PetscLogEventActivate(USER_EVENT));
57   PetscCall(PetscLogEventBegin(USER_EVENT, 0, 0, 0, 0));
58   PetscCall(PetscSleep(0.5));
59   PetscCall(PetscLogEventEnd(USER_EVENT, 0, 0, 0, 0));
60 
61   /*
62      We test event logging imbalance
63   */
64   PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
65   if (rank == 0) PetscCall(PetscSleep(0.5));
66   PetscCall(PetscLogEventSync(USER_EVENT, PETSC_COMM_WORLD));
67   PetscCall(PetscLogEventBegin(USER_EVENT, 0, 0, 0, 0));
68   PetscCallMPI(MPI_Barrier(PETSC_COMM_WORLD));
69   PetscCall(PetscSleep(0.5));
70   PetscCall(PetscLogEventEnd(USER_EVENT, 0, 0, 0, 0));
71 
72   PetscCall(PetscFinalize());
73   return 0;
74 }
75 
76 /*TEST
77 
78    build:
79      requires: defined(PETSC_USE_LOG)
80 
81    test:
82 
83 TEST*/
84