.\" Copyright (c) 1983 Regents of the University of California.
.\" All rights reserved. The Berkeley software License Agreement
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.\" @(#)gprof.1 6.1 (Berkeley) %G%
gprof \- display call graph profile data
[ options ] [ a.out [ gmon.out ... ] ]
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
default) which is created by programs
which are compiled with the
That option also links in versions of the library routines
which are compiled for profiling.
is read and correlated with the
If more than one profile file is specified,
output shows the sum of the profile information in the given profile files.
First, a flat profile is given,
similar to that provided by
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
A second 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 listing of the members of the cycle and their contributions to the
time and call counts of the cycle.
The following options are available:
suppresses the printing of statically declared functions.
If this option is given, all relevant information about the static function
time samples, calls to other functions, calls from other functions)
belongs to the function loaded just before the static function in the
supresses the printing of a description of each field in the profile.
the static call graph of the program is discovered by a heuristic
which examines the text space of the object file.
Static-only parents or children are indicated
suppresses the printing of the graph profile entry for routine
(unless they have other ancestors that aren't suppressed).
suppresses the printing of the graph profile entry for routine
above, and also excludes the time spent in
(and its descendants) from the total and percentage time computations.
prints the graph profile entry of only the specified routine
prints the graph profile entry of only the routine
above) and also uses only the times of the printed routines
in total time and percentage computations.
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
to accumulate profile data across several runs of an
displays routines which have zero usage (as indicated by call counts
This is useful in conjunction with the
option for discovering which routines were never called.
the namelist and text space.
dynamic call graph and profile.
summarized dynamic call graph and profile.
monitor(3), profil(2), cc(1), prof(1)
``gprof: A Call Graph Execution Profiler'', by
Graham, S.L., Kessler, P.B., McKusick, M.K.;
.IR "Proceedings of the SIGPLAN '82 Symposium on Compiler Construction" ,
SIGPLAN Notices, Vol. 17, No. 6, pp. 120-126, June 1982.
Beware of quantization errors.
The granularity of the sampling is shown, but remains
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
function is directly proportional to the number of times that
Parents which are not themselves profiled will have the time of
their profiled children propagated to them, but they will appear
to be spontaneously 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
or return normally for the profiling information to be saved