2: /*
3: This is to allow one to measure CPU time usage of their job,
4: NOT real time usage. Do not use this for reported timings, speedup etc.
5: */
7: #include <petscsys.h>
8: #include <petsctime.h>
9: #include <ctype.h>
10: #include <sys/stat.h>
11: #if defined(PETSC_HAVE_SYS_UTSNAME_H)
12: #include <sys/utsname.h>
13: #endif
14: #if defined(PETSC_HAVE_TIME_H)
15: #include <time.h>
16: #endif
17: #if defined(PETSC_HAVE_SYS_SYSTEMINFO_H)
18: #include <sys/systeminfo.h>
19: #endif
21: #if defined(PETSC_HAVE_SYS_TIMES_H)
23: #include <sys/times.h>
24: PetscErrorCode PetscGetCPUTime(PetscLogDouble *t)
25: {
26: struct tms temp;
28: times(&temp);
29: *t = ((double)temp.tms_utime) / ((double)CLOCKS_PER_SEC);
30: return 0;
31: }
33: #elif defined(PETSC_HAVE_CLOCK)
35: #include <time.h>
37: PetscErrorCode PetscGetCPUTime(PetscLogDouble *t)
38: {
39: *t = ((double)clock()) / ((double)CLOCKS_PER_SEC);
40: return 0;
41: }
43: #else
45: #include <sys/time.h>
46: #include <sys/resource.h>
48: /*@
49: PetscGetCPUTime - Returns the CPU time in seconds used by the process.
51: Not Collective
53: Output Parameter:
54: . t - Time in seconds charged to the process.
56: Example:
57: .vb
58: #include <petscsys.h>
59: ...
60: PetscLogDouble t1, t2;
62: PetscGetCPUTime(&t1);
63: ... code to time ...
64: PetscGetCPUTime(&t2);
65: printf("Code took %f CPU seconds\n", t2-t1);
66: .ve
68: Level: intermediate
70: Note:
71: One should use the -log_view option of
72: PETSc for profiling. The CPU time is NOT a realistic number to
73: use since it does not include the time for message passing etc.
74: Also on many systems the accuracy is only on the order of microseconds.
76: .seealso: `PetscTime()`, `PetscLogView()`
77: @*/
78: PetscErrorCode PetscGetCPUTime(PetscLogDouble *t)
79: {
80: static struct rusage temp;
81: PetscLogDouble foo, foo1;
83: getrusage(RUSAGE_SELF, &temp);
84: foo = temp.ru_utime.tv_sec; /* seconds */
85: foo1 = temp.ru_utime.tv_usec; /* uSecs */
86: *t = foo + foo1 * 1.0e-6;
87: return 0;
88: }
90: #endif