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.\" $FreeBSD$ 34.\" 35.Dd June 6, 1993 36.Dt GPROF 1 37.Os BSD 4.2 38.Sh NAME 39.Nm gprof 40.Nd display call graph profile data 41.Sh SYNOPSIS 42.Nm gprof 43.Op options 44.Op Ar a.out Op Ar a.out.gmon ... 45.Sh DESCRIPTION 46.Nm Gprof 47produces an execution profile of C, Pascal, or Fortran77 programs. 48The effect of called routines is incorporated in the profile of each caller. 49The profile data is taken from the call graph profile file 50which is created by programs that are compiled with the 51.Fl pg 52option of 53.Xr cc 1 , 54.Xr pc 1 , 55and 56.Xr f77 1 . 57The 58.Fl pg 59option also links in versions of the library routines 60that are compiled for profiling. 61.Nm Gprof 62reads the given object file (the default is 63.Pa a.out) 64and establishes the relation between it's symbol table 65and the call graph profile. The default graph profile file name is the name 66of the executable with the suffix 67.Pa .gmon 68appended. 69If more than one profile file is specified, 70the 71.Nm gprof 72output shows the sum of the profile information in the given profile files. 73.Pp 74.Nm Gprof 75calculates the amount of time spent in each routine. 76Next, these times are propagated along the edges of the call graph. 77Cycles are discovered, and calls into a cycle are made to share the time 78of the cycle. 79The first listing shows the functions 80sorted according to the time they represent 81including the time of their call graph descendents. 82Below each function entry is shown its (direct) call graph children, 83and how their times are propagated to this function. 84A similar display above the function shows how this function's time and the 85time of its descendents is propagated to its (direct) call graph parents. 86.Pp 87Cycles are also shown, with an entry for the cycle as a whole and 88a listing of the members of the cycle and their contributions to the 89time and call counts of the cycle. 90.Pp 91Second, a flat profile is given, 92similar to that provided by 93.Xr prof 1 . 94This listing gives the total execution times, the call counts, 95the time in msec or usec the call spent in the routine itself, and 96the time in msec or usec the call spent in the routine itself including 97its descendents. 98.Pp 99Finally, an index of the function names is provided. 100.Pp 101The following options are available: 102.Bl -tag -width Fl 103.It Fl a 104Suppresses the printing of statically declared functions. 105If this option is given, all relevant information about the static function 106(e.g., time samples, calls to other functions, calls from other functions) 107belongs to the function loaded just before the static function in the 108.Pa a.out 109file. 110.It Fl b 111Suppresses the printing of a description of each field in the profile. 112.It Fl c 113The static call graph of the program is discovered by a heuristic 114that examines the text space of the object file. 115Static-only parents or children are shown 116with call counts of 0. 117This option is not supported on some architectures. 118.It Fl C Ar count 119Find a minimal set of arcs that can be broken to eliminate all cycles with 120.Ar count 121or more members. 122Caution: the algorithm used to break cycles is exponential, 123so using this option may cause 124.Nm gprof 125to run for a very long time. 126.It Fl e Ar name 127Suppresses the printing of the graph profile entry for routine 128.Ar name 129and all its descendants 130(unless they have other ancestors that aren't suppressed). 131More than one 132.Fl e 133option may be given. 134Only one 135.Ar name 136may be given with each 137.Fl e 138option. 139.It Fl E Ar name 140Suppresses the printing of the graph profile entry for routine 141.Ar name 142(and its descendants) as 143.Fl e , 144above, and also excludes the time spent in 145.Ar name 146(and its descendants) from the total and percentage time computations. 147(For example, 148.Fl E 149.Ar mcount 150.Fl E 151.Ar mcleanup 152is the default.) 153.It Fl f Ar name 154Prints the graph profile entry of only the specified routine 155.Ar name 156and its descendants. 157More than one 158.Fl f 159option may be given. 160Only one 161.Ar name 162may be given with each 163.Fl f 164option. 165.It Fl F Ar name 166Prints the graph profile entry of only the routine 167.Ar name 168and its descendants (as 169.Fl f , 170above) and also uses only the times of the printed routines 171in total time and percentage computations. 172More than one 173.Fl F 174option may be given. 175Only one 176.Ar name 177may be given with each 178.Fl F 179option. 180The 181.Fl F 182option 183overrides 184the 185.Fl E 186option. 187.It Fl k Ar fromname Ar toname 188Will delete any arcs from routine 189.Ar fromname 190to routine 191.Ar toname . 192This can be used to break undesired cycles. 193More than one 194.Fl k 195option may be given. 196Only one pair of routine names may be given with each 197.Fl k 198option. 199.It Fl l 200Suppresses the printing of the call-graph profile. 201.It Fl L 202Suppresses the printing of the flat profile. 203.It Fl s 204A profile file 205.Pa gmon.sum 206is produced that represents 207the sum of the profile information in all the specified profile files. 208This summary profile file may be given to later 209executions of gprof (probably also with a 210.Fl s ) 211to accumulate profile data across several runs of an 212.Pa a.out 213file. 214.It Fl u 215Suppresses the printing of functions whose names are not visible to 216C programs. For the ELF object format, this means names that 217contain the 218.Ql \&. 219character. For the a.out object format, it means names that do not 220begin with a 221.Ql _ 222character. 223All relevant information about such functions belongs to the 224(non-suppressed) function with the next lowest address. 225This is useful for eliminating "functions" that are just labels 226inside other functions. 227.It Fl z 228Displays routines that have zero usage (as shown by call counts 229and accumulated time). 230This is useful with the 231.Fl c 232option for discovering which routines were never called. 233.El 234.Sh FILES 235.Bl -tag -width a.out.gmon -compact 236.It Pa a.out 237The namelist and text space. 238.It Pa a.out.gmon 239Dynamic call graph and profile. 240.It Pa gmon.sum 241Summarized dynamic call graph and profile. 242.El 243.Sh SEE ALSO 244.Xr cc 1 , 245.Xr profil 2 , 246.Xr clocks 7 247.\" .Xr monitor 3 , 248.\" .Xr prof 1 249.Rs 250.%T "An Execution Profiler for Modular Programs" 251.%A S. Graham 252.%A P. Kessler 253.%A M. McKusick 254.%J "Software - Practice and Experience" 255.%V 13 256.%P pp. 671-685 257.%D 1983 258.Re 259.Rs 260.%T "gprof: A Call Graph Execution Profiler" 261.%A S. Graham 262.%A P. Kessler 263.%A M. McKusick 264.%J "Proceedings of the SIGPLAN '82 Symposium on Compiler Construction, SIGPLAN Notices" 265.%V 17 266.%N 6 267.%P pp. 120-126 268.%D June 1982 269.Re 270.Sh HISTORY 271The 272.Nm gprof 273profiler 274appeared in 275.Bx 4.2 . 276.Sh BUGS 277The granularity of the sampling is shown, but remains 278statistical at best. 279We assume that the time for each execution of a function 280can be expressed by the total time for the function divided 281by the number of times the function is called. 282Thus the time propagated along the call graph arcs to the function's 283parents is directly proportional to the number of times that 284arc is traversed. 285.Pp 286Parents that are not themselves profiled will have the time of 287their profiled children propagated to them, but they will appear 288to be spontaneously invoked in the call graph listing, and will 289not have their time propagated further. 290Similarly, signal catchers, even though profiled, will appear 291to be spontaneous (although for more obscure reasons). 292Any profiled children of signal catchers should have their times 293propagated properly, unless the signal catcher was invoked during 294the execution of the profiling routine, in which case all is lost. 295.Pp 296The profiled program must call 297.Xr exit 3 298or return normally for the profiling information to be saved 299in the graph profile file. 300