1GPROF(1) GNU GPROF(1)
2
6 gprof - display call graph profile data
7
9 gprof [ -[abcDhilLrsTvwxyz] ] [ -[ACeEfFJnNOpPqQRStZ][name] ]
10 [ -I dirs ] [ -d[num] ] [ -k from/to ]
11 [ -m min-count ] [ -R map_file ] [ -t table-length ]
12 [ --[no-]annotated-source[=name] ]
13 [ --[no-]exec-counts[=name] ]
14 [ --[no-]flat-profile[=name] ] [ --[no-]graph[=name] ]
15 [ --[no-]time=name] [ --all-lines ] [ --brief ]
16 [ --debug[=level] ] [ --function-ordering ]
17 [ --file-ordering map_file ] [ --directory-path=dirs ]
18 [ --display-unused-functions ] [ --file-format=name ]
19 [ --file-info ] [ --help ] [ --line ] [ --inline-file-names ]
20 [ --min-count=n ] [ --no-static ] [ --print-path ]
21 [ --separate-files ] [ --static-call-graph ] [ --sum ]
22 [ --table-length=len ] [ --traditional ] [ --version ]
23 [ --width=n ] [ --ignore-non-functions ]
24 [ --demangle[=STYLE] ] [ --no-demangle ]
25 [--external-symbol-table=name]
26 [ image-file ] [ profile-file ... ]
27
29 "gprof" produces an execution profile of C, Pascal, or Fortran77
30 programs. The effect of called routines is incorporated in the profile
31 of each caller. The profile data is taken from the call graph profile
32 file (gmon.out default) which is created by programs that are compiled
33 with the -pg option of "cc", "pc", and "f77". The -pg option also
34 links in versions of the library routines that are compiled for
35 profiling. "Gprof" reads the given object file (the default is
36 "a.out") and establishes the relation between its symbol table and the
37 call graph profile from gmon.out. If more than one profile file is
38 specified, the "gprof" output shows the sum of the profile information
39 in the given profile files.
40 "Gprof" calculates the amount of time spent in each routine. Next,
42 these times are propagated along the edges of the call graph. Cycles
43 are discovered, and calls into a cycle are made to share the time of
44 the cycle.
45 Several forms of output are available from the analysis.
47 The flat profile shows how much time your program spent in each
49 function, and how many times that function was called. If you simply
50 want to know which functions burn most of the cycles, it is stated
51 concisely here.
52 The call graph shows, for each function, which functions called it,
54 which other functions it called, and how many times. There is also an
55 estimate of how much time was spent in the subroutines of each
56 function. This can suggest places where you might try to eliminate
57 function calls that use a lot of time.
58 The annotated source listing is a copy of the program's source code,
60 labeled with the number of times each line of the program was executed.
61
63 These options specify which of several output formats "gprof" should
64 produce.
65 Many of these options take an optional symspec to specify functions to
67 be included or excluded. These options can be specified multiple
68 times, with different symspecs, to include or exclude sets of symbols.
69 Specifying any of these options overrides the default (-p -q), which
71 prints a flat profile and call graph analysis for all functions.
72 "-A[symspec]"
74 "--annotated-source[=symspec]"
75 The -A option causes "gprof" to print annotated source code. If
76 symspec is specified, print output only for matching symbols.
77 "-b"
79 "--brief"
80 If the -b option is given, "gprof" doesn't print the verbose blurbs
81 that try to explain the meaning of all of the fields in the tables.
82 This is useful if you intend to print out the output, or are tired
83 of seeing the blurbs.
84 "-C[symspec]"
86 "--exec-counts[=symspec]"
87 The -C option causes "gprof" to print a tally of functions and the
88 number of times each was called. If symspec is specified, print
89 tally only for matching symbols.
90 If the profile data file contains basic-block count records,
92 specifying the -l option, along with -C, will cause basic-block
93 execution counts to be tallied and displayed.
94 "-i"
96 "--file-info"
97 The -i option causes "gprof" to display summary information about
98 the profile data file(s) and then exit. The number of histogram,
99 call graph, and basic-block count records is displayed.
100 "-I dirs"
102 "--directory-path=dirs"
103 The -I option specifies a list of search directories in which to
104 find source files. Environment variable GPROF_PATH can also be
105 used to convey this information. Used mostly for annotated source
106 output.
107 "-J[symspec]"
109 "--no-annotated-source[=symspec]"
110 The -J option causes "gprof" not to print annotated source code.
111 If symspec is specified, "gprof" prints annotated source, but
112 excludes matching symbols.
113 "-L"
115 "--print-path"
116 Normally, source filenames are printed with the path component
117 suppressed. The -L option causes "gprof" to print the full
118 pathname of source filenames, which is determined from symbolic
119 debugging information in the image file and is relative to the
120 directory in which the compiler was invoked.
121 "-p[symspec]"
123 "--flat-profile[=symspec]"
124 The -p option causes "gprof" to print a flat profile. If symspec
125 is specified, print flat profile only for matching symbols.
126 "-P[symspec]"
128 "--no-flat-profile[=symspec]"
129 The -P option causes "gprof" to suppress printing a flat profile.
130 If symspec is specified, "gprof" prints a flat profile, but
131 excludes matching symbols.
132 "-q[symspec]"
134 "--graph[=symspec]"
135 The -q option causes "gprof" to print the call graph analysis. If
136 symspec is specified, print call graph only for matching symbols
137 and their children.
138 "-Q[symspec]"
140 "--no-graph[=symspec]"
141 The -Q option causes "gprof" to suppress printing the call graph.
142 If symspec is specified, "gprof" prints a call graph, but excludes
143 matching symbols.
144 "-t"
146 "--table-length=num"
147 The -t option causes the num most active source lines in each
148 source file to be listed when source annotation is enabled. The
149 default is 10.
150 "-y"
152 "--separate-files"
153 This option affects annotated source output only. Normally,
154 "gprof" prints annotated source files to standard-output. If this
155 option is specified, annotated source for a file named
156 path/filename is generated in the file filename-ann. If the
157 underlying file system would truncate filename-ann so that it
158 overwrites the original filename, "gprof" generates annotated
159 source in the file filename.ann instead (if the original file name
160 has an extension, that extension is replaced with .ann).
161 "-Z[symspec]"
163 "--no-exec-counts[=symspec]"
164 The -Z option causes "gprof" not to print a tally of functions and
165 the number of times each was called. If symspec is specified,
166 print tally, but exclude matching symbols.
167 "-r"
169 "--function-ordering"
170 The --function-ordering option causes "gprof" to print a suggested
171 function ordering for the program based on profiling data. This
172 option suggests an ordering which may improve paging, tlb and cache
173 behavior for the program on systems which support arbitrary
174 ordering of functions in an executable.
175 The exact details of how to force the linker to place functions in
177 a particular order is system dependent and out of the scope of this
178 manual.
179 "-R map_file"
181 "--file-ordering map_file"
182 The --file-ordering option causes "gprof" to print a suggested .o
183 link line ordering for the program based on profiling data. This
184 option suggests an ordering which may improve paging, tlb and cache
185 behavior for the program on systems which do not support arbitrary
186 ordering of functions in an executable.
187 Use of the -a argument is highly recommended with this option.
189 The map_file argument is a pathname to a file which provides
191 function name to object file mappings. The format of the file is
192 similar to the output of the program "nm".
193 c-parse.o:00000000 T yyparse
195 c-parse.o:00000004 C yyerrflag
196 c-lang.o:00000000 T maybe_objc_method_name
197 c-lang.o:00000000 T print_lang_statistics
198 c-lang.o:00000000 T recognize_objc_keyword
199 c-decl.o:00000000 T print_lang_identifier
200 c-decl.o:00000000 T print_lang_type
201 ...
202 To create a map_file with GNU "nm", type a command like "nm
204 --extern-only --defined-only -v --print-file-name program-name".
205 "-T"
207 "--traditional"
208 The -T option causes "gprof" to print its output in "traditional"
209 BSD style.
210 "-w width"
212 "--width=width"
213 Sets width of output lines to width. Currently only used when
214 printing the function index at the bottom of the call graph.
215 "-x"
217 "--all-lines"
218 This option affects annotated source output only. By default, only
219 the lines at the beginning of a basic-block are annotated. If this
220 option is specified, every line in a basic-block is annotated by
221 repeating the annotation for the first line. This behavior is
222 similar to "tcov"'s -a.
223 "--demangle[=style]"
225 "--no-demangle"
226 These options control whether C++ symbol names should be demangled
227 when printing output. The default is to demangle symbols. The
228 "--no-demangle" option may be used to turn off demangling.
229 Different compilers have different mangling styles. The optional
230 demangling style argument can be used to choose an appropriate
231 demangling style for your compiler.
232 Analysis Options
234 "-a"
235 "--no-static"
236 The -a option causes "gprof" to suppress the printing of statically
237 declared (private) functions. (These are functions whose names are
238 not listed as global, and which are not visible outside the
239 file/function/block where they were defined.) Time spent in these
240 functions, calls to/from them, etc., will all be attributed to the
241 function that was loaded directly before it in the executable file.
242 This option affects both the flat profile and the call graph.
243 "-c"
245 "--static-call-graph"
246 The -c option causes the call graph of the program to be augmented
247 by a heuristic which examines the text space of the object file and
248 identifies function calls in the binary machine code. Since normal
249 call graph records are only generated when functions are entered,
250 this option identifies children that could have been called, but
251 never were. Calls to functions that were not compiled with
252 profiling enabled are also identified, but only if symbol table
253 entries are present for them. Calls to dynamic library routines
254 are typically not found by this option. Parents or children
255 identified via this heuristic are indicated in the call graph with
256 call counts of 0.
257 "-D"
259 "--ignore-non-functions"
260 The -D option causes "gprof" to ignore symbols which are not known
261 to be functions. This option will give more accurate profile data
262 on systems where it is supported (Solaris and HPUX for example).
263 "-k from/to"
265 The -k option allows you to delete from the call graph any arcs
266 from symbols matching symspec from to those matching symspec to.
267 "-l"
269 "--line"
270 The -l option enables line-by-line profiling, which causes
271 histogram hits to be charged to individual source code lines,
272 instead of functions. This feature only works with programs
273 compiled by older versions of the "gcc" compiler. Newer versions
274 of "gcc" are designed to work with the "gcov" tool instead.
275 If the program was compiled with basic-block counting enabled, this
277 option will also identify how many times each line of code was
278 executed. While line-by-line profiling can help isolate where in a
279 large function a program is spending its time, it also
280 significantly increases the running time of "gprof", and magnifies
281 statistical inaccuracies.
282 "--inline-file-names"
284 This option causes "gprof" to print the source file after each
285 symbol in both the flat profile and the call graph. The full path
286 to the file is printed if used with the -L option.
287 "-m num"
289 "--min-count=num"
290 This option affects execution count output only. Symbols that are
291 executed less than num times are suppressed.
292 "-nsymspec"
294 "--time=symspec"
295 The -n option causes "gprof", in its call graph analysis, to only
296 propagate times for symbols matching symspec.
297 "-Nsymspec"
299 "--no-time=symspec"
300 The -n option causes "gprof", in its call graph analysis, not to
301 propagate times for symbols matching symspec.
302 "-Sfilename"
304 "--external-symbol-table=filename"
305 The -S option causes "gprof" to read an external symbol table file,
306 such as /proc/kallsyms, rather than read the symbol table from the
307 given object file (the default is "a.out"). This is useful for
308 profiling kernel modules.
309 "-z"
311 "--display-unused-functions"
312 If you give the -z option, "gprof" will mention all functions in
313 the flat profile, even those that were never called, and that had
314 no time spent in them. This is useful in conjunction with the -c
315 option for discovering which routines were never called.
316 Miscellaneous Options
318 "-d[num]"
319 "--debug[=num]"
320 The -d num option specifies debugging options. If num is not
321 specified, enable all debugging.
322 "-h"
324 "--help"
325 The -h option prints command line usage.
326 "-Oname"
328 "--file-format=name"
329 Selects the format of the profile data files. Recognized formats
330 are auto (the default), bsd, 4.4bsd, magic, and prof (not yet
331 supported).
332 "-s"
334 "--sum"
335 The -s option causes "gprof" to summarize the information in the
336 profile data files it read in, and write out a profile data file
337 called gmon.sum, which contains all the information from the
338 profile data files that "gprof" read in. The file gmon.sum may be
339 one of the specified input files; the effect of this is to merge
340 the data in the other input files into gmon.sum.
341 Eventually you can run "gprof" again without -s to analyze the
343 cumulative data in the file gmon.sum.
344 "-v"
346 "--version"
347 The -v flag causes "gprof" to print the current version number, and
348 then exit.
349 Deprecated Options
351 These options have been replaced with newer versions that use symspecs.
352 "-e function_name"
354 The -e function option tells "gprof" to not print information about
355 the function function_name (and its children...) in the call graph.
356 The function will still be listed as a child of any functions that
357 call it, but its index number will be shown as [not printed]. More
358 than one -e option may be given; only one function_name may be
359 indicated with each -e option.
360 "-E function_name"
362 The "-E function" option works like the "-e" option, but time spent
363 in the function (and children who were not called from anywhere
364 else), will not be used to compute the percentages-of-time for the
365 call graph. More than one -E option may be given; only one
366 function_name may be indicated with each -E option.
367 "-f function_name"
369 The -f function option causes "gprof" to limit the call graph to
370 the function function_name and its children (and their
371 children...). More than one -f option may be given; only one
372 function_name may be indicated with each -f option.
373 "-F function_name"
375 The -F function option works like the "-f" option, but only time
376 spent in the function and its children (and their children...) will
377 be used to determine total-time and percentages-of-time for the
378 call graph. More than one -F option may be given; only one
379 function_name may be indicated with each -F option. The -F option
380 overrides the -E option.
381
383 "a.out"
384 the namelist and text space.
385 "gmon.out"
387 dynamic call graph and profile.
388 "gmon.sum"
390 summarized dynamic call graph and profile.
391
393 The granularity of the sampling is shown, but remains statistical at
394 best. We assume that the time for each execution of a function can be
395 expressed by the total time for the function divided by the number of
396 times the function is called. Thus the time propagated along the call
397 graph arcs to the function's parents is directly proportional to the
398 number of times that arc is traversed.
399 Parents that are not themselves profiled will have the time of their
401 profiled children propagated to them, but they will appear to be
402 spontaneously invoked in the call graph listing, and will not have
403 their time propagated further. Similarly, signal catchers, even though
404 profiled, will appear to be spontaneous (although for more obscure
405 reasons). Any profiled children of signal catchers should have their
406 times propagated properly, unless the signal catcher was invoked during
407 the execution of the profiling routine, in which case all is lost.
408 The profiled program must call "exit"(2) or return normally for the
410 profiling information to be saved in the gmon.out file.
411
413 monitor(3), profil(2), cc(1), prof(1), and the Info entry for gprof.
414 "An Execution Profiler for Modular Programs", by S. Graham, P. Kessler,
416 M. McKusick; Software - Practice and Experience, Vol. 13, pp. 671-685,
417 1983.
418 "gprof: A Call Graph Execution Profiler", by S. Graham, P. Kessler, M.
420 McKusick; Proceedings of the SIGPLAN '82 Symposium on Compiler
421 Construction, SIGPLAN Notices, Vol. 17, No 6, pp. 120-126, June 1982.
422
424 Copyright (c) 1988-2022 Free Software Foundation, Inc.
425 Permission is granted to copy, distribute and/or modify this document
427 under the terms of the GNU Free Documentation License, Version 1.3 or
428 any later version published by the Free Software Foundation; with no
429 Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
430 Texts. A copy of the license is included in the section entitled "GNU
431 Free Documentation License".
432binutils-2.39 2022-08-05 GPROF(1)