1 /* 2 This is to allow one to measure CPU time usage of their job, 3 NOT real time usage. Do not use this for reported timings, speedup etc. 4 */ 5 6 #include <petscsys.h> /*I "petscsys.h" I*/ 7 #include <petsctime.h> /*I "petsctime.h" I*/ 8 #include <ctype.h> 9 #include <sys/stat.h> 10 #if defined(PETSC_HAVE_SYS_UTSNAME_H) 11 #include <sys/utsname.h> 12 #endif 13 #if defined(PETSC_HAVE_TIME_H) 14 #include <time.h> 15 #endif 16 #if defined(PETSC_HAVE_SYS_SYSTEMINFO_H) 17 #include <sys/systeminfo.h> 18 #endif 19 20 #if defined(PETSC_HAVE_SYS_TIMES_H) 21 22 #include <sys/times.h> 23 PetscErrorCode PetscGetCPUTime(PetscLogDouble *t) 24 { 25 struct tms temp; 26 27 PetscFunctionBegin; 28 times(&temp); 29 *t = ((double)temp.tms_utime) / ((double)CLOCKS_PER_SEC); 30 PetscFunctionReturn(PETSC_SUCCESS); 31 } 32 33 #elif defined(PETSC_HAVE_CLOCK) 34 35 #include <time.h> 36 37 PetscErrorCode PetscGetCPUTime(PetscLogDouble *t) 38 { 39 PetscFunctionBegin; 40 *t = ((double)clock()) / ((double)CLOCKS_PER_SEC); 41 PetscFunctionReturn(PETSC_SUCCESS); 42 } 43 44 #else 45 46 #include <sys/time.h> 47 #include <sys/resource.h> 48 49 /*@ 50 PetscGetCPUTime - Returns the CPU time in seconds used by the process. 51 52 Not Collective 53 54 Output Parameter: 55 . t - Time in seconds charged to the process. 56 57 Example: 58 .vb 59 #include <petscsys.h> 60 ... 61 PetscLogDouble t1, t2; 62 63 PetscCall(PetscGetCPUTime(&t1)); 64 ... code to time ... 65 PetscCall(PetscGetCPUTime(&t2)); 66 printf("Code took %f CPU seconds\n", t2-t1); 67 .ve 68 69 Level: intermediate 70 71 Note: 72 One should use the -log_view option of 73 PETSc for profiling. The CPU time is NOT a realistic number to 74 use since it does not include the time for message passing etc. 75 Also on many systems the accuracy is only on the order of microseconds. 76 77 .seealso: `PetscTime()`, `PetscLogView()` 78 @*/ 79 PetscErrorCode PetscGetCPUTime(PetscLogDouble *t) 80 { 81 static struct rusage temp; 82 PetscLogDouble foo, foo1; 83 84 PetscFunctionBegin; 85 getrusage(RUSAGE_SELF, &temp); 86 foo = temp.ru_utime.tv_sec; /* seconds */ 87 foo1 = temp.ru_utime.tv_usec; /* uSecs */ 88 *t = foo + foo1 * 1.0e-6; 89 PetscFunctionReturn(PETSC_SUCCESS); 90 } 91 92 #endif 93