xref: /petsc/src/sys/tutorials/ex3.c (revision 609caa7c8c030312b00807b4f015fd827bb80932)
1 static char help[] = "Augmenting PETSc profiling by add events.\n\
2 Run this program with one of the\n\
3 following options to generate logging information:  -log, -log_view,\n\
4 -log_all.  The PETSc routines automatically log event times and flops,\n\
5 so this monitoring is intended solely for users to employ in application\n\
6 codes.\n\n";
7 
8 /*
9   Include "petscsys.h" so that we can use PETSc profiling routines.
10 */
11 #include <petscsys.h>
12 #include <petscviewer.h>
13 
main(int argc,char ** argv)14 int main(int argc, char **argv)
15 {
16   PetscMPIInt   rank;
17   int           i, imax = 10000, icount;
18   PetscLogEvent USER_EVENT, check_USER_EVENT;
19 
20   PetscFunctionBeginUser;
21   PetscCall(PetscInitialize(&argc, &argv, NULL, help));
22 
23   /*
24      Create a new user-defined event.
25       - Note that PetscLogEventRegister() returns to the user a unique
26         integer event number, which should then be used for profiling
27         the event via PetscLogEventBegin() and PetscLogEventEnd().
28       - The user can also optionally log floating point operations
29         with the routine PetscLogFlops().
30   */
31   PetscCall(PetscLogEventRegister("User event", PETSC_VIEWER_CLASSID, &USER_EVENT));
32   PetscCall(PetscLogEventGetId("User event", &check_USER_EVENT));
33   PetscCheck(USER_EVENT == check_USER_EVENT, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Event Ids do not match");
34 
35   PetscCall(PetscLogEventBegin(USER_EVENT, 0, 0, 0, 0));
36   icount = 0;
37   for (i = 0; i < imax; i++) icount++;
38   (void)icount;
39   PetscCall(PetscLogFlops(imax));
40   PetscCall(PetscSleep(0.5));
41   PetscCall(PetscLogEventEnd(USER_EVENT, 0, 0, 0, 0));
42 
43   /*
44      We disable the logging of an event.
45 
46   */
47   PetscCall(PetscLogEventDeactivate(USER_EVENT));
48   PetscCall(PetscLogEventBegin(USER_EVENT, 0, 0, 0, 0));
49   PetscCall(PetscSleep(0.5));
50   PetscCall(PetscLogEventEnd(USER_EVENT, 0, 0, 0, 0));
51 
52   /*
53      We next enable the logging of an event
54   */
55   PetscCall(PetscLogEventActivate(USER_EVENT));
56   PetscCall(PetscLogEventBegin(USER_EVENT, 0, 0, 0, 0));
57   PetscCall(PetscSleep(0.5));
58   PetscCall(PetscLogEventEnd(USER_EVENT, 0, 0, 0, 0));
59 
60   /*
61      We test event logging imbalance
62   */
63   PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
64   if (rank == 0) PetscCall(PetscSleep(0.5));
65   PetscCall(PetscLogEventSync(USER_EVENT, PETSC_COMM_WORLD));
66   PetscCall(PetscLogEventBegin(USER_EVENT, 0, 0, 0, 0));
67   PetscCallMPI(MPI_Barrier(PETSC_COMM_WORLD));
68   PetscCall(PetscSleep(0.5));
69   PetscCall(PetscLogEventEnd(USER_EVENT, 0, 0, 0, 0));
70 
71   PetscCall(PetscFinalize());
72   return 0;
73 }
74 
75 /*TEST
76 
77    build:
78      requires: defined(PETSC_USE_LOG)
79 
80    test:
81      output_file: output/empty.out
82 
83 TEST*/
84