4.3BSD-Reno/share/man/cat1/gprof.0
GPROF(1) UNIX Reference Manual GPROF(1)
NNAAMMEE
ggpprrooff - display call graph profile data
SSYYNNOOPPSSIISS
ggpprrooff [options] [_a._o_u_t [_g_m_o_n._o_u_t ...]]
DDEESSCCRRIIPPTTIIOONN
ggpprrooff produces an execution profile of C, Pascal, or Fortran77 programs.
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 that are compiled with
the --ppgg option of cc(1), pc(1), and f77(1). The --ppgg option also links in
versions of the library routines that are compiled for profiling. GGpprrooff
reads the given object file (the default is _a._o_u_t) and establishes the
relation between it's symbol table and the call graph profile from
_g_m_o_n._o_u_t. If more than one profile file is specified, the ggpprrooff output
shows the sum of the profile information in the given profile files.
GGpprrooff calculates the amount of time spent in each routine. 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 cy-
cle. The first listing shows the functions sorted according 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 list-
ing of the members of the cycle and their contributions to the time and
call counts of the cycle.
Second, a flat profile is given, similar to that provided by prof(1).
This listing gives the total execution times, the call counts, the time
in milleseconds the call spent in the routine itself, and the time in
milleseconds the call spent in the routine itself including its descen-
dents.
Finally, an index of the function names is provided.
The following options are available:
--aa 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 be-
fore the static function in the _a._o_u_t file.
--bb suppresses the printing of a description of each field in the
profile.
--cc the static call graph of the program is discovered by a heuris-
tic that examines the text space of the object file. Static-
only parents or children are shown with call counts of 0.
--ee _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 --ee option may be given.
Only one _n_a_m_e may be given with each --ee option.
--EE _n_a_m_e suppresses the printing of the graph profile entry for routine
_n_a_m_e (and its descendants) as --ee, above, and also excludes the
time spent in _n_a_m_e (and its descendants) from the total and
percentage time computations. (For example, --EE _m_c_o_u_n_t --EE
_m_c_l_e_a_n_u_p is the default.)
--ff _n_a_m_e prints the graph profile entry of only the specified routine
_n_a_m_e and its descendants. More than one --ff option may be
given. Only one _n_a_m_e may be given with each --ff option.
--FF _n_a_m_e prints the graph profile entry of only the routine _n_a_m_e and its
descendants (as --ff, above) and also uses only the times of the
printed routines in total time and percentage computations.
More than one --FF option may be given. Only one _n_a_m_e may be
given with each --FF option. The --FF option overrides the --EE op-
tion.
--kk _f_r_o_m_n_a_m_e _t_o_n_a_m_e
will delete any arcs from routine _f_r_o_m_n_a_m_e to routine _t_o_n_a_m_e.
This can be used to break undesired cycles. More than one --kk
option may be given. Only one pair of routine names may be
given with each --kk option.
--ss a profile file _g_m_o_n._s_u_m is produced that represents the sum of
the profile information in all the specified profile files.
This summary profile file may be given to later executions of
gprof (probably also with a --ss) to accumulate profile data
across several runs of an _a._o_u_t file.
--zz displays routines that have zero usage (as shown by call counts
and accumulated time). This is useful with the --cc option for
discovering which routines were never called.
FFIILLEESS
_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.
SSEEEE AALLSSOO
monitor(3), profil(2), cc(1), prof(1)
_A_n _E_x_e_c_u_t_i_o_n _P_r_o_f_i_l_e_r _f_o_r _M_o_d_u_l_a_r _P_r_o_g_r_a_m_s, by S. Graham, P. Kessler, M.
McKusick; Software - Practice and Experience, Vol. 13, pp. 671-685,
1983.
_g_p_r_o_f: _A _C_a_l_l _G_r_a_p_h _E_x_e_c_u_t_i_o_n _P_r_o_f_i_l_e_r, by S. Graham, P. Kessler, M.
McKusick; Proceedings of the SIGPLAN '82 Symposium on Compiler Construc-
tion, SIGPLAN Notices, Vol. 17, No 6, pp. 120-126, June 1982.
HHIISSTTOORRYY
GGpprrooff appeared in 4.2 BSD.
BBUUGGSS
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 the function's parents is directly proportional to the
number of times that arc is traversed.
Parents that are not themselves profiled will have the time of their pro-
filed children propagated to them, but they will appear to be spontane-
ously invoked in the call graph listing, and will not have their time
propagated further. Similarly, signal catchers, even though profiled,
will appear to be spontaneous (although for more obscure reasons). 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 exit(2) or return normally for the profil-
ing information to be saved in the _g_m_o_n._o_u_t file.