1.\" Copyright (c) 1983, 1990 The Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" %sccs.include.redist.man% 5.\" 6.\" @(#)gprof.1 6.6 (Berkeley) 07/24/90 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.Tw Fl 76.Tp 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.Tp Fl b 84suppresses the printing of a description of each field in the profile. 85.Tp 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.Tc Fl e 91.Ws 92.Ar name 93.Cx 94suppresses the printing of the graph profile entry for routine 95.Ar name 96and all its descendants 97(unless they have other ancestors that aren't suppressed). 98More than one 99.Fl e 100option may be given. 101Only one 102.Ar name 103may be given with each 104.Fl e 105option. 106.Tc Fl E 107.Ws 108.Ar name 109.Cx 110suppresses the printing of the graph profile entry for routine 111.Ar name 112(and its descendants) as 113.Fl e , 114above, and also excludes the time spent in 115.Ar name 116(and its descendants) from the total and percentage time computations. 117(For example, 118.Fl E 119.Ar mcount 120.Fl E 121.Ar mcleanup 122is the default.) 123.Tc Fl f 124.Ws 125.Ar name 126.Cx 127prints the graph profile entry of only the specified routine 128.Ar name 129and its descendants. 130More than one 131.Fl f 132option may be given. 133Only one 134.Ar name 135may be given with each 136.Fl f 137option. 138.Tc Fl F 139.Ws 140.Ar name 141.Cx 142prints the graph profile entry of only the routine 143.Ar name 144and its descendants (as 145.Fl f , 146above) and also uses only the times of the printed routines 147in total time and percentage computations. 148More than one 149.Fl F 150option may be given. 151Only one 152.Ar name 153may be given with each 154.Fl F 155option. 156The 157.Fl F 158option 159overrides 160the 161.Fl E 162option. 163.Tc Fl k 164.Ws 165.Ar fromname 166.Ws 167.Ar toname 168.Cx 169will delete any arcs from routine 170.Ar fromname 171to routine 172.Ar toname . 173This can be used to break undesired cycles. 174More than one 175.Fl k 176option may be given. 177Only one pair of routine names may be given with each 178.Fl k 179option. 180.Tp Fl s 181a profile file 182.Pa gmon.sum 183is produced that represents 184the sum of the profile information in all the specified profile files. 185This summary profile file may be given to later 186executions of gprof (probably also with a 187.Fl s ) 188to accumulate profile data across several runs of an 189.Pa a.out 190file. 191.Tp Fl z 192displays routines that have zero usage (as shown by call counts 193and accumulated time). 194This is useful with the 195.Fl c 196option for discovering which routines were never called. 197.Tp 198.Sh FILES 199.Dw gmon.sum 200.Di L 201.Dp Pa a.out 202the namelist and text space. 203.Dp Pa gmon.out 204dynamic call graph and profile. 205.Dp Pa gmon.sum 206summarized dynamic call graph and profile. 207.Dp 208.Sh SEE ALSO 209.Xr monitor 3 , 210.Xr profil 2 , 211.Xr cc 1 , 212.Xr prof 1 213.br 214.Em An Execution Profiler for Modular Programs , 215by 216S. Graham, P. Kessler, M. McKusick; 217Software - Practice and Experience, 218Vol. 13, pp. 671-685, 1983. 219.br 220.Em gprof: A Call Graph Execution Profiler , 221by S. Graham, P. Kessler, M. McKusick; 222Proceedings of the SIGPLAN '82 Symposium on Compiler Construction, 223SIGPLAN Notices, Vol. 17, No 6, pp. 120-126, June 1982. 224.Sh HISTORY 225.Nm Gprof 226appeared in 4.2 BSD. 227.Sh BUGS 228The granularity of the sampling is shown, but remains 229statistical at best. 230We assume that the time for each execution of a function 231can be expressed by the total time for the function divided 232by the number of times the function is called. 233Thus the time propagated along the call graph arcs to the function's 234parents is directly proportional to the number of times that 235arc is traversed. 236.Pp 237Parents that are not themselves profiled will have the time of 238their profiled children propagated to them, but they will appear 239to be spontaneously invoked in the call graph listing, and will 240not have their time propagated further. 241Similarly, signal catchers, even though profiled, will appear 242to be spontaneous (although for more obscure reasons). 243Any profiled children of signal catchers should have their times 244propagated properly, unless the signal catcher was invoked during 245the execution of the profiling routine, in which case all is lost. 246.Pp 247The profiled program must call 248.Xr exit 2 249or return normally for the profiling information to be saved 250in the 251.Pa gmon.out 252file. 253