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. 116This option is not supported on some architectures. 117.It Fl C Ar count 118Find a minimal set of arcs that can be broken to eliminate all cycles with 119.Ar count 120or more members. 121Caution: the algorithm used to break cycles is exponential, 122so using this option may cause 123.Nm gprof 124to run for a very long time. 125.It Fl e Ar name 126Suppresses the printing of the graph profile entry for routine 127.Ar name 128and all its descendants 129(unless they have other ancestors that aren't suppressed). 130More than one 131.Fl e 132option may be given. 133Only one 134.Ar name 135may be given with each 136.Fl e 137option. 138.It Fl E Ar name 139Suppresses the printing of the graph profile entry for routine 140.Ar name 141(and its descendants) as 142.Fl e , 143above, and also excludes the time spent in 144.Ar name 145(and its descendants) from the total and percentage time computations. 146(For example, 147.Fl E 148.Ar mcount 149.Fl E 150.Ar mcleanup 151is the default.) 152.It Fl f Ar name 153Prints the graph profile entry of only the specified routine 154.Ar name 155and its descendants. 156More than one 157.Fl f 158option may be given. 159Only one 160.Ar name 161may be given with each 162.Fl f 163option. 164.It Fl F Ar name 165Prints the graph profile entry of only the routine 166.Ar name 167and its descendants (as 168.Fl f , 169above) and also uses only the times of the printed routines 170in total time and percentage computations. 171More than one 172.Fl F 173option may be given. 174Only one 175.Ar name 176may be given with each 177.Fl F 178option. 179The 180.Fl F 181option 182overrides 183the 184.Fl E 185option. 186.It Fl k Ar fromname Ar toname 187Will delete any arcs from routine 188.Ar fromname 189to routine 190.Ar toname . 191This can be used to break undesired cycles. 192More than one 193.Fl k 194option may be given. 195Only one pair of routine names may be given with each 196.Fl k 197option. 198.It Fl l 199Suppresses the printing of the call-graph profile. 200.It Fl L 201Suppresses the printing of the flat profile. 202.It Fl s 203A profile file 204.Pa gmon.sum 205is produced that represents 206the sum of the profile information in all the specified profile files. 207This summary profile file may be given to later 208executions of gprof (probably also with a 209.Fl s ) 210to accumulate profile data across several runs of an 211.Pa a.out 212file. 213.It Fl u 214Suppresses the printing of functions whose names are not visible to 215C programs. For the ELF object format, this means names that 216contain the 217.Ql \&. 218character. For the a.out object format, it means names that do not 219begin with a 220.Ql _ 221character. 222All relevant information about such functions belongs to the 223(non-suppressed) function with the next lowest address. 224This is useful for eliminating "functions" that are just labels 225inside other functions. 226.It Fl z 227Displays routines that have zero usage (as shown by call counts 228and accumulated time). 229This is useful with the 230.Fl c 231option for discovering which routines were never called. 232.El 233.Sh FILES 234.Bl -tag -width gmon.sum -compact 235.It Pa a.out 236The namelist and text space. 237.It Pa gmon.out 238Dynamic call graph and profile. 239.It Pa gmon.sum 240Summarized dynamic call graph and profile. 241.El 242.Sh SEE ALSO 243.Xr cc 1 , 244.Xr profil 2 , 245.Xr clocks 7 246.\" .Xr monitor 3 , 247.\" .Xr prof 1 248.Rs 249.%T "An Execution Profiler for Modular Programs" 250.%A S. Graham 251.%A P. Kessler 252.%A M. McKusick 253.%J "Software - Practice and Experience" 254.%V 13 255.%P pp. 671-685 256.%D 1983 257.Re 258.Rs 259.%T "gprof: A Call Graph Execution Profiler" 260.%A S. Graham 261.%A P. Kessler 262.%A M. McKusick 263.%J "Proceedings of the SIGPLAN '82 Symposium on Compiler Construction, SIGPLAN Notices" 264.%V 17 265.%N 6 266.%P pp. 120-126 267.%D June 1982 268.Re 269.Sh HISTORY 270The 271.Nm gprof 272profiler 273appeared in 274.Bx 4.2 . 275.Sh BUGS 276The granularity of the sampling is shown, but remains 277statistical at best. 278We assume that the time for each execution of a function 279can be expressed by the total time for the function divided 280by the number of times the function is called. 281Thus the time propagated along the call graph arcs to the function's 282parents is directly proportional to the number of times that 283arc is traversed. 284.Pp 285Parents that are not themselves profiled will have the time of 286their profiled children propagated to them, but they will appear 287to be spontaneously invoked in the call graph listing, and will 288not have their time propagated further. 289Similarly, signal catchers, even though profiled, will appear 290to be spontaneous (although for more obscure reasons). 291Any profiled children of signal catchers should have their times 292propagated properly, unless the signal catcher was invoked during 293the execution of the profiling routine, in which case all is lost. 294.Pp 295The profiled program must call 296.Xr exit 3 297or return normally for the profiling information to be saved 298in the 299.Pa gmon.out 300file. 301