1.\" Copyright (c) 1983, 1990, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)gprof.1 8.1 (Berkeley) 6/6/93 33.\" 34.Dd June 6, 1993 35.Dt GPROF 1 36.Os BSD 4.2 37.Sh NAME 38.Nm gprof 39.Nd display call graph profile data 40.Sh SYNOPSIS 41.Nm gprof 42.Op options 43.Op Ar a.out Op Ar gmon.out ... 44.Sh DESCRIPTION 45.Nm Gprof 46produces an execution profile of C, Pascal, or Fortran77 programs. 47The effect of called routines is incorporated in the profile of each caller. 48The profile data is taken from the call graph profile file 49.Pf ( Pa gmon.out 50default) which is created by programs 51that are compiled with the 52.Fl pg 53option of 54.Xr cc 1 , 55.Xr pc 1 , 56and 57.Xr f77 1 . 58The 59.Fl pg 60option also links in versions of the library routines 61that are compiled for profiling. 62.Nm Gprof 63reads the given object file (the default is 64.Pa a.out) 65and establishes the relation between it's symbol table 66and the call graph profile from 67.Pa gmon.out . 68If more than one profile file is specified, 69the 70.Nm gprof 71output shows the sum of the profile information in the given profile files. 72.Pp 73.Nm Gprof 74calculates the amount of time spent in each routine. 75Next, these times are propagated along the edges of the call graph. 76Cycles are discovered, and calls into a cycle are made to share the time 77of the cycle. 78The first listing shows the functions 79sorted according to the time they represent 80including the time of their call graph descendents. 81Below each function entry is shown its (direct) call graph children, 82and how their times are propagated to this function. 83A similar display above the function shows how this function's time and the 84time of its descendents is propagated to its (direct) call graph parents. 85.Pp 86Cycles are also shown, with an entry for the cycle as a whole and 87a listing of the members of the cycle and their contributions to the 88time and call counts of the cycle. 89.Pp 90Second, a flat profile is given, 91similar to that provided by 92.Xr prof 1 . 93This listing gives the total execution times, the call counts, 94the time in msec or usec the call spent in the routine itself, and 95the time in msec or usec the call spent in the routine itself including 96its descendents. 97.Pp 98Finally, an index of the function names is provided. 99.Pp 100The following options are available: 101.Bl -tag -width Fl 102.It Fl a 103Suppresses the printing of statically declared functions. 104If this option is given, all relevant information about the static function 105(e.g., time samples, calls to other functions, calls from other functions) 106belongs to the function loaded just before the static function in the 107.Pa a.out 108file. 109.It Fl b 110Suppresses the printing of a description of each field in the profile. 111.It Fl c 112The static call graph of the program is discovered by a heuristic 113that examines the text space of the object file. 114Static-only parents or children are shown 115with call counts of 0. 116.It Fl C Ar count 117Find a minimal set of arcs that can be broken to eliminate all cycles with 118.Ar count 119or more members. 120Caution: the algorithm used to break cycles is exponential, 121so using this option may cause 122.Nm gprof 123to run for a very long time. 124.It Fl e Ar name 125Suppresses the printing of the graph profile entry for routine 126.Ar name 127and all its descendants 128(unless they have other ancestors that aren't suppressed). 129More than one 130.Fl e 131option may be given. 132Only one 133.Ar name 134may be given with each 135.Fl e 136option. 137.It Fl E Ar name 138Suppresses the printing of the graph profile entry for routine 139.Ar name 140(and its descendants) as 141.Fl e , 142above, and also excludes the time spent in 143.Ar name 144(and its descendants) from the total and percentage time computations. 145(For example, 146.Fl E 147.Ar mcount 148.Fl E 149.Ar mcleanup 150is the default.) 151.It Fl f Ar name 152Prints the graph profile entry of only the specified routine 153.Ar name 154and its descendants. 155More than one 156.Fl f 157option may be given. 158Only one 159.Ar name 160may be given with each 161.Fl f 162option. 163.It Fl F Ar name 164Prints the graph profile entry of only the routine 165.Ar name 166and its descendants (as 167.Fl f , 168above) and also uses only the times of the printed routines 169in total time and percentage computations. 170More than one 171.Fl F 172option may be given. 173Only one 174.Ar name 175may be given with each 176.Fl F 177option. 178The 179.Fl F 180option 181overrides 182the 183.Fl E 184option. 185.It Fl k Ar fromname Ar toname 186Will delete any arcs from routine 187.Ar fromname 188to routine 189.Ar toname . 190This can be used to break undesired cycles. 191More than one 192.Fl k 193option may be given. 194Only one pair of routine names may be given with each 195.Fl k 196option. 197.It Fl l 198Suppresses the printing of the call-graph profile. 199.It Fl L 200Suppresses the printing of the flat profile. 201.It Fl s 202A profile file 203.Pa gmon.sum 204is produced that represents 205the sum of the profile information in all the specified profile files. 206This summary profile file may be given to later 207executions of gprof (probably also with a 208.Fl s ) 209to accumulate profile data across several runs of an 210.Pa a.out 211file. 212.It Fl u 213Suppresses the printing of functions whose name does not begin with 214an underscore. 215All relevant information about such functions belongs to the 216(non-suppressed) function with the next lowest address. 217This is useful for eliminating "functions" that are just labels 218inside other functions. 219.It Fl z 220Displays routines that have zero usage (as shown by call counts 221and accumulated time). 222This is useful with the 223.Fl c 224option for discovering which routines were never called. 225.El 226.Sh FILES 227.Bl -tag -width gmon.sum -compact 228.It Pa a.out 229The namelist and text space. 230.It Pa gmon.out 231Dynamic call graph and profile. 232.It Pa gmon.sum 233Summarized dynamic call graph and profile. 234.El 235.Sh SEE ALSO 236.Xr cc 1 , 237.Xr profil 2 , 238.Xr clocks 7 239.\" .Xr monitor 3 , 240.\" .Xr prof 1 241.Rs 242.%T "An Execution Profiler for Modular Programs" 243.%A S. Graham 244.%A P. Kessler 245.%A M. McKusick 246.%J "Software - Practice and Experience" 247.%V 13 248.%P pp. 671-685 249.%D 1983 250.Re 251.Rs 252.%T "gprof: A Call Graph Execution Profiler" 253.%A S. Graham 254.%A P. Kessler 255.%A M. McKusick 256.%J "Proceedings of the SIGPLAN '82 Symposium on Compiler Construction, SIGPLAN Notices" 257.%V 17 258.%N 6 259.%P pp. 120-126 260.%D June 1982 261.Re 262.Sh HISTORY 263The 264.Nm gprof 265profiler 266appeared in 267.Bx 4.2 . 268.Sh BUGS 269The granularity of the sampling is shown, but remains 270statistical at best. 271We assume that the time for each execution of a function 272can be expressed by the total time for the function divided 273by the number of times the function is called. 274Thus the time propagated along the call graph arcs to the function's 275parents is directly proportional to the number of times that 276arc is traversed. 277.Pp 278Parents that are not themselves profiled will have the time of 279their profiled children propagated to them, but they will appear 280to be spontaneously invoked in the call graph listing, and will 281not have their time propagated further. 282Similarly, signal catchers, even though profiled, will appear 283to be spontaneous (although for more obscure reasons). 284Any profiled children of signal catchers should have their times 285propagated properly, unless the signal catcher was invoked during 286the execution of the profiling routine, in which case all is lost. 287.Pp 288The profiled program must call 289.Xr exit 3 290or return normally for the profiling information to be saved 291in the 292.Pa gmon.out 293file. 294