1.\" Copyright (c) 1983, 1990 The Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" %sccs.include.redist.roff% 5.\" 6.\" @(#)gprof.1 6.8 (Berkeley) 07/24/91 7.\" 8.Dd 9.Dt GPROF 1 10.Os BSD 4.2 11.Sh NAME 12.Nm gprof 13.Nd display call graph profile data 14.Sh SYNOPSIS 15.Nm gprof 16.Op options 17.Op Ar a.out Op Ar gmon.out ... 18.Sh DESCRIPTION 19.Nm Gprof 20produces an execution profile of C, Pascal, or Fortran77 programs. 21The effect of called routines is incorporated in the profile of each caller. 22The profile data is taken from the call graph profile file 23.Pf ( Pa gmon.out 24default) which is created by programs 25that are compiled with the 26.Fl pg 27option of 28.Xr cc 1 , 29.Xr pc 1 , 30and 31.Xr f77 1 . 32The 33.Fl pg 34option also links in versions of the library routines 35that are compiled for profiling. 36.Nm Gprof 37reads the given object file (the default is 38.Pa a.out) 39and establishes the relation between it's symbol table 40and the call graph profile from 41.Pa gmon.out . 42If more than one profile file is specified, 43the 44.Nm gprof 45output shows the sum of the profile information in the given profile files. 46.Pp 47.Nm Gprof 48calculates the amount of time spent in each routine. 49Next, these times are propagated along the edges of the call graph. 50Cycles are discovered, and calls into a cycle are made to share the time 51of the cycle. 52The first listing shows the functions 53sorted according to the time they represent 54including the time of their call graph descendents. 55Below each function entry is shown its (direct) call graph children, 56and how their times are propagated to this function. 57A similar display above the function shows how this function's time and the 58time of its descendents is propagated to its (direct) call graph parents. 59.Pp 60Cycles are also shown, with an entry for the cycle as a whole and 61a listing of the members of the cycle and their contributions to the 62time and call counts of the cycle. 63.Pp 64Second, a flat profile is given, 65similar to that provided by 66.Xr prof 1 . 67This listing gives the total execution times, the call counts, 68the time in milleseconds the call spent in the routine itself, and 69the time in milleseconds the call spent in the routine itself including 70its descendents. 71.Pp 72Finally, an index of the function names is provided. 73.Pp 74The following options are available: 75.Bl -tag -width Fl 76.It Fl a 77Suppresses the printing of statically declared functions. 78If this option is given, all relevant information about the static function 79(e.g., time samples, calls to other functions, calls from other functions) 80belongs to the function loaded just before the static function in the 81.Pa a.out 82file. 83.It Fl b 84Suppresses the printing of a description of each field in the profile. 85.It Fl c 86The static call graph of the program is discovered by a heuristic 87that examines the text space of the object file. 88Static-only parents or children are shown 89with call counts of 0. 90.It Fl e Ar name 91Suppresses the printing of the graph profile entry for routine 92.Ar name 93and all its descendants 94(unless they have other ancestors that aren't suppressed). 95More than one 96.Fl e 97option may be given. 98Only one 99.Ar name 100may be given with each 101.Fl e 102option. 103.It Fl E Ar name 104Suppresses the printing of the graph profile entry for routine 105.Ar name 106(and its descendants) as 107.Fl e , 108above, and also excludes the time spent in 109.Ar name 110(and its descendants) from the total and percentage time computations. 111(For example, 112.Fl E 113.Ar mcount 114.Fl E 115.Ar mcleanup 116is the default.) 117.It Fl f Ar name 118Prints the graph profile entry of only the specified routine 119.Ar name 120and its descendants. 121More than one 122.Fl f 123option may be given. 124Only one 125.Ar name 126may be given with each 127.Fl f 128option. 129.It Fl F Ar name 130Prints the graph profile entry of only the routine 131.Ar name 132and its descendants (as 133.Fl f , 134above) and also uses only the times of the printed routines 135in total time and percentage computations. 136More than one 137.Fl F 138option may be given. 139Only one 140.Ar name 141may be given with each 142.Fl F 143option. 144The 145.Fl F 146option 147overrides 148the 149.Fl E 150option. 151.It Fl k Ar fromname Ar toname 152Will delete any arcs from routine 153.Ar fromname 154to routine 155.Ar toname . 156This can be used to break undesired cycles. 157More than one 158.Fl k 159option may be given. 160Only one pair of routine names may be given with each 161.Fl k 162option. 163.It Fl s 164A profile file 165.Pa gmon.sum 166is produced that represents 167the sum of the profile information in all the specified profile files. 168This summary profile file may be given to later 169executions of gprof (probably also with a 170.Fl s ) 171to accumulate profile data across several runs of an 172.Pa a.out 173file. 174.It Fl z 175Displays routines that have zero usage (as shown by call counts 176and accumulated time). 177This is useful with the 178.Fl c 179option for discovering which routines were never called. 180.El 181.Sh FILES 182.Bl -tag -width gmon.sum -compact 183.It Pa a.out 184The namelist and text space. 185.It Pa gmon.out 186Dynamic call graph and profile. 187.It Pa gmon.sum 188Summarized dynamic call graph and profile. 189.El 190.Sh SEE ALSO 191.Xr monitor 3 , 192.Xr profil 2 , 193.Xr cc 1 , 194.Xr prof 1 195.Rs 196.%T "An Execution Profiler for Modular Programs" 197.%A S. Graham 198.%A P. Kessler 199.%A M. McKusick 200.%J "Software - Practice and Experience" 201.%V 13 202.%P pp. 671-685 203.%D 1983 204.Re 205.Rs 206.%T "gprof: A Call Graph Execution Profiler" 207.%A S. Graham 208.%A P. Kessler 209.%A M. McKusick 210.%J "Proceedings of the SIGPLAN '82 Symposium on Compiler Construction, SIGPLAN Notices" 211.%V 17 212.%N 6 213.%P pp. 120-126 214.%D June 1982 215.Re 216.Sh HISTORY 217The 218.Nm gprof 219profiler 220appeared in 221.Bx 4.2 . 222.Sh BUGS 223The granularity of the sampling is shown, but remains 224statistical at best. 225We assume that the time for each execution of a function 226can be expressed by the total time for the function divided 227by the number of times the function is called. 228Thus the time propagated along the call graph arcs to the function's 229parents is directly proportional to the number of times that 230arc is traversed. 231.Pp 232Parents that are not themselves profiled will have the time of 233their profiled children propagated to them, but they will appear 234to be spontaneously invoked in the call graph listing, and will 235not have their time propagated further. 236Similarly, signal catchers, even though profiled, will appear 237to be spontaneous (although for more obscure reasons). 238Any profiled children of signal catchers should have their times 239propagated properly, unless the signal catcher was invoked during 240the execution of the profiling routine, in which case all is lost. 241.Pp 242The profiled program must call 243.Xr exit 2 244or return normally for the profiling information to be saved 245in the 246.Pa gmon.out 247file. 248