GPROF(1) GPROF(1) NAME gprof - display call graph profile data SYNOPSIS gprof [ options ] [ a.out [ gmon.out ... ] ] DESCRIPTION _g_p_r_o_f produces an execution profile of C, Pascal, or Fortran77 pro‐ grams. The effect of called routines is incorporated in the profile of each caller. The profile data is taken from the call graph profile file (_g_m_o_n_._o_u_t default) which is created by programs which are compiled with the -pg option of _c_c, _p_c, and _f_7_7. That option also links in ver‐ sions of the library routines which are compiled for profiling. The symbol table in the named object file (_a_._o_u_t default) is read and cor‐ related with the call graph profile file. If more than one profile file is specified, the _g_p_r_o_f output shows the sum of the profile infor‐ mation in the given profile files. First, a flat profile is given, similar to that provided by _p_r_o_f(1). This listing gives the total execution times and call counts for each of the functions in the program, sorted by decreasing time. Next, these times are propagated along the edges of the call graph. Cycles are discovered, and calls into a cycle are made to share the time of the cycle. A second listing shows the functions sorted accord‐ ing to the time they represent including the time of their call graph descendents. Below each function entry is shown its (direct) call graph children, and how their times are propagated to this function. A similar display above the function shows how this function’s time and the time of its descendents is propagated to its (direct) call graph parents. Cycles are also shown, with an entry for the cycle as a whole and a listing of the members of the cycle and their contributions to the time and call counts of the cycle. The following options are available: -a suppresses the printing of statically declared functions. If this option is given, all relevant information about the static function (_e_._g_._, time samples, calls to other functions, calls from other functions) belongs to the function loaded just before the static function in the _a_._o_u_t file. -b supresses the printing of a description of each field in the profile. -c the static call graph of the program is discovered by a heuris‐ tic which examines the text space of the object file. Static- only parents or children are indicated with call counts of 0. -e _n_a_m_e suppresses the printing of the graph profile entry for routine _n_a_m_e and all its descendants (unless they have other ancestors that aren’t suppressed). More than one -e option may be given. Only one _n_a_m_e may be given with each -e option. -E _n_a_m_e suppresses the printing of the graph profile entry for routine _n_a_m_e (and its descendants) as -e, above, and also excludes the time spent in _n_a_m_e (and its descendants) from the total and per‐ centage time computations. (For example, -E _m_c_o_u_n_t -E _m_c_l_e_a_n_u_p is the default.) -f _n_a_m_e prints the graph profile entry of only the specified routine _n_a_m_e and its descendants. More than one -f option may be given. Only one _n_a_m_e may be given with each -f option. -F _n_a_m_e prints the graph profile entry of only the routine _n_a_m_e and its descendants (as -f, above) and also uses only the times of the printed routines in total time and percentage computations. More than one -F option may be given. Only one _n_a_m_e may be given with each -F option. The -F option overrides the -E option. -s a profile file _g_m_o_n_._s_u_m is produced which represents the sum of the profile information in all the specified profile files. This summary profile file may be given to subsequent executions of gprof (probably also with a -s) to accumulate profile data across several runs of an _a_._o_u_t file. -z displays routines which have zero usage (as indicated by call counts and accumulated time). This is useful in conjunction with the -c option for discovering which routines were never called. FILES _a_._o_u_t the namelist and text space. _g_m_o_n_._o_u_t dynamic call graph and profile. _g_m_o_n_._s_u_m summarized dynamic call graph and profile. SEE ALSO monitor(3), profil(2), cc(1), prof(1) ‘‘gprof: A Call Graph Execution Profiler’’, by Graham, S.L., Kessler, P.B., McKusick, M.K.; _P_r_o_c_e_e_d_i_n_g_s _o_f _t_h_e _S_I_G_P_L_A_N _’_8_2 _S_y_m_p_o_s_i_u_m _o_n _C_o_m_‐ _p_i_l_e_r _C_o_n_s_t_r_u_c_t_i_o_n, SIGPLAN Notices, Vol. 17, No. 6, pp. 120-126, June 1982. BUGS Beware of quantization errors. The granularity of the sampling is shown, but remains statistical at best. We assume that the time for each execution of a function can be expressed by the total time for the function divided by the number of times the function is called. Thus the time propagated along the call graph arcs to parents of that func‐ tion is directly proportional to the number of times that arc is tra‐ versed. Parents which are not themselves profiled will have the time of their profiled children propagated to them, but they will appear to be spon‐ taneously invoked in the call graph listing, and will not have their time propagated further. Similarly, signal catchers, even though pro‐ filed, will appear to be spontaneous (although for more obscure rea‐ sons). Any profiled children of signal catchers should have their times propagated properly, unless the signal catcher was invoked during the execution of the profiling routine, in which case all is lost. The profiled program must call _e_x_i_t(2) or return normally for the pro‐ filing information to be saved in the gmon.out file. 4.2 Berkeley Distribution April 29, 1985 GPROF(1)