1GPROF(1) GNU GPROF(1)
2
6 gprof - display call graph profile data
7
9 gprof [ -[abcDhilLrsTvwxyz] ] [ -[ABCeEfFJnNOpPqQRStZ][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 "-B"
86 The -B option causes "gprof" to print the call graph analysis.
87 "-C[symspec]"
89 "--exec-counts[=symspec]"
90 The -C option causes "gprof" to print a tally of functions and the
91 number of times each was called. If symspec is specified, print
92 tally only for matching symbols.
93 If the profile data file contains basic-block count records,
95 specifying the -l option, along with -C, will cause basic-block
96 execution counts to be tallied and displayed.
97 "-i"
99 "--file-info"
100 The -i option causes "gprof" to display summary information about
101 the profile data file(s) and then exit. The number of histogram,
102 call graph, and basic-block count records is displayed.
103 "-I dirs"
105 "--directory-path=dirs"
106 The -I option specifies a list of search directories in which to
107 find source files. Environment variable GPROF_PATH can also be
108 used to convey this information. Used mostly for annotated source
109 output.
110 "-J[symspec]"
112 "--no-annotated-source[=symspec]"
113 The -J option causes "gprof" not to print annotated source code.
114 If symspec is specified, "gprof" prints annotated source, but
115 excludes matching symbols.
116 "-L"
118 "--print-path"
119 Normally, source filenames are printed with the path component
120 suppressed. The -L option causes "gprof" to print the full
121 pathname of source filenames, which is determined from symbolic
122 debugging information in the image file and is relative to the
123 directory in which the compiler was invoked.
124 "-p[symspec]"
126 "--flat-profile[=symspec]"
127 The -p option causes "gprof" to print a flat profile. If symspec
128 is specified, print flat profile only for matching symbols.
129 "-P[symspec]"
131 "--no-flat-profile[=symspec]"
132 The -P option causes "gprof" to suppress printing a flat profile.
133 If symspec is specified, "gprof" prints a flat profile, but
134 excludes matching symbols.
135 "-q[symspec]"
137 "--graph[=symspec]"
138 The -q option causes "gprof" to print the call graph analysis. If
139 symspec is specified, print call graph only for matching symbols
140 and their children.
141 "-Q[symspec]"
143 "--no-graph[=symspec]"
144 The -Q option causes "gprof" to suppress printing the call graph.
145 If symspec is specified, "gprof" prints a call graph, but excludes
146 matching symbols.
147 "-t"
149 "--table-length=num"
150 The -t option causes the num most active source lines in each
151 source file to be listed when source annotation is enabled. The
152 default is 10.
153 "-y"
155 "--separate-files"
156 This option affects annotated source output only. Normally,
157 "gprof" prints annotated source files to standard-output. If this
158 option is specified, annotated source for a file named
159 path/filename is generated in the file filename-ann. If the
160 underlying file system would truncate filename-ann so that it
161 overwrites the original filename, "gprof" generates annotated
162 source in the file filename.ann instead (if the original file name
163 has an extension, that extension is replaced with .ann).
164 "-Z[symspec]"
166 "--no-exec-counts[=symspec]"
167 The -Z option causes "gprof" not to print a tally of functions and
168 the number of times each was called. If symspec is specified,
169 print tally, but exclude matching symbols.
170 "-r"
172 "--function-ordering"
173 The --function-ordering option causes "gprof" to print a suggested
174 function ordering for the program based on profiling data. This
175 option suggests an ordering which may improve paging, tlb and cache
176 behavior for the program on systems which support arbitrary
177 ordering of functions in an executable.
178 The exact details of how to force the linker to place functions in
180 a particular order is system dependent and out of the scope of this
181 manual.
182 "-R map_file"
184 "--file-ordering map_file"
185 The --file-ordering option causes "gprof" to print a suggested .o
186 link line ordering for the program based on profiling data. This
187 option suggests an ordering which may improve paging, tlb and cache
188 behavior for the program on systems which do not support arbitrary
189 ordering of functions in an executable.
190 Use of the -a argument is highly recommended with this option.
192 The map_file argument is a pathname to a file which provides
194 function name to object file mappings. The format of the file is
195 similar to the output of the program "nm".
196 c-parse.o:00000000 T yyparse
198 c-parse.o:00000004 C yyerrflag
199 c-lang.o:00000000 T maybe_objc_method_name
200 c-lang.o:00000000 T print_lang_statistics
201 c-lang.o:00000000 T recognize_objc_keyword
202 c-decl.o:00000000 T print_lang_identifier
203 c-decl.o:00000000 T print_lang_type
204 ...
205 To create a map_file with GNU "nm", type a command like "nm
207 --extern-only --defined-only -v --print-file-name program-name".
208 "-T"
210 "--traditional"
211 The -T option causes "gprof" to print its output in "traditional"
212 BSD style.
213 "-w width"
215 "--width=width"
216 Sets width of output lines to width. Currently only used when
217 printing the function index at the bottom of the call graph.
218 "-x"
220 "--all-lines"
221 This option affects annotated source output only. By default, only
222 the lines at the beginning of a basic-block are annotated. If this
223 option is specified, every line in a basic-block is annotated by
224 repeating the annotation for the first line. This behavior is
225 similar to "tcov"'s -a.
226 "--demangle[=style]"
228 "--no-demangle"
229 These options control whether C++ symbol names should be demangled
230 when printing output. The default is to demangle symbols. The
231 "--no-demangle" option may be used to turn off demangling.
232 Different compilers have different mangling styles. The optional
233 demangling style argument can be used to choose an appropriate
234 demangling style for your compiler.
235 Analysis Options
237 "-a"
238 "--no-static"
239 The -a option causes "gprof" to suppress the printing of statically
240 declared (private) functions. (These are functions whose names are
241 not listed as global, and which are not visible outside the
242 file/function/block where they were defined.) Time spent in these
243 functions, calls to/from them, etc., will all be attributed to the
244 function that was loaded directly before it in the executable file.
245 This option affects both the flat profile and the call graph.
246 "-c"
248 "--static-call-graph"
249 The -c option causes the call graph of the program to be augmented
250 by a heuristic which examines the text space of the object file and
251 identifies function calls in the binary machine code. Since normal
252 call graph records are only generated when functions are entered,
253 this option identifies children that could have been called, but
254 never were. Calls to functions that were not compiled with
255 profiling enabled are also identified, but only if symbol table
256 entries are present for them. Calls to dynamic library routines
257 are typically not found by this option. Parents or children
258 identified via this heuristic are indicated in the call graph with
259 call counts of 0.
260 "-D"
262 "--ignore-non-functions"
263 The -D option causes "gprof" to ignore symbols which are not known
264 to be functions. This option will give more accurate profile data
265 on systems where it is supported (Solaris and HPUX for example).
266 "-k from/to"
268 The -k option allows you to delete from the call graph any arcs
269 from symbols matching symspec from to those matching symspec to.
270 "-l"
272 "--line"
273 The -l option enables line-by-line profiling, which causes
274 histogram hits to be charged to individual source code lines,
275 instead of functions. This feature only works with programs
276 compiled by older versions of the "gcc" compiler. Newer versions
277 of "gcc" are designed to work with the "gcov" tool instead.
278 If the program was compiled with basic-block counting enabled, this
280 option will also identify how many times each line of code was
281 executed. While line-by-line profiling can help isolate where in a
282 large function a program is spending its time, it also
283 significantly increases the running time of "gprof", and magnifies
284 statistical inaccuracies.
285 "--inline-file-names"
287 This option causes "gprof" to print the source file after each
288 symbol in both the flat profile and the call graph. The full path
289 to the file is printed if used with the -L option.
290 "-m num"
292 "--min-count=num"
293 This option affects execution count output only. Symbols that are
294 executed less than num times are suppressed.
295 "-nsymspec"
297 "--time=symspec"
298 The -n option causes "gprof", in its call graph analysis, to only
299 propagate times for symbols matching symspec.
300 "-Nsymspec"
302 "--no-time=symspec"
303 The -n option causes "gprof", in its call graph analysis, not to
304 propagate times for symbols matching symspec.
305 "-Sfilename"
307 "--external-symbol-table=filename"
308 The -S option causes "gprof" to read an external symbol table file,
309 such as /proc/kallsyms, rather than read the symbol table from the
310 given object file (the default is "a.out"). This is useful for
311 profiling kernel modules.
312 "-z"
314 "--display-unused-functions"
315 If you give the -z option, "gprof" will mention all functions in
316 the flat profile, even those that were never called, and that had
317 no time spent in them. This is useful in conjunction with the -c
318 option for discovering which routines were never called.
319 Miscellaneous Options
321 "-d[num]"
322 "--debug[=num]"
323 The -d num option specifies debugging options. If num is not
324 specified, enable all debugging.
325 "-h"
327 "--help"
328 The -h option prints command line usage.
329 "-Oname"
331 "--file-format=name"
332 Selects the format of the profile data files. Recognized formats
333 are auto (the default), bsd, 4.4bsd, magic, and prof (not yet
334 supported).
335 "-s"
337 "--sum"
338 The -s option causes "gprof" to summarize the information in the
339 profile data files it read in, and write out a profile data file
340 called gmon.sum, which contains all the information from the
341 profile data files that "gprof" read in. The file gmon.sum may be
342 one of the specified input files; the effect of this is to merge
343 the data in the other input files into gmon.sum.
344 Eventually you can run "gprof" again without -s to analyze the
346 cumulative data in the file gmon.sum.
347 "-v"
349 "--version"
350 The -v flag causes "gprof" to print the current version number, and
351 then exit.
352 Deprecated Options
354 These options have been replaced with newer versions that use symspecs.
355 "-e function_name"
357 The -e function option tells "gprof" to not print information about
358 the function function_name (and its children...) in the call graph.
359 The function will still be listed as a child of any functions that
360 call it, but its index number will be shown as [not printed]. More
361 than one -e option may be given; only one function_name may be
362 indicated with each -e option.
363 "-E function_name"
365 The "-E function" option works like the "-e" option, but time spent
366 in the function (and children who were not called from anywhere
367 else), will not be used to compute the percentages-of-time for the
368 call graph. More than one -E option may be given; only one
369 function_name may be indicated with each -E option.
370 "-f function_name"
372 The -f function option causes "gprof" to limit the call graph to
373 the function function_name and its children (and their
374 children...). More than one -f option may be given; only one
375 function_name may be indicated with each -f option.
376 "-F function_name"
378 The -F function option works like the "-f" option, but only time
379 spent in the function and its children (and their children...) will
380 be used to determine total-time and percentages-of-time for the
381 call graph. More than one -F option may be given; only one
382 function_name may be indicated with each -F option. The -F option
383 overrides the -E option.
384
386 "a.out"
387 the namelist and text space.
388 "gmon.out"
390 dynamic call graph and profile.
391 "gmon.sum"
393 summarized dynamic call graph and profile.
394
396 The granularity of the sampling is shown, but remains statistical at
397 best. We assume that the time for each execution of a function can be
398 expressed by the total time for the function divided by the number of
399 times the function is called. Thus the time propagated along the call
400 graph arcs to the function's parents is directly proportional to the
401 number of times that arc is traversed.
402 Parents that are not themselves profiled will have the time of their
404 profiled children propagated to them, but they will appear to be
405 spontaneously invoked in the call graph listing, and will not have
406 their time propagated further. Similarly, signal catchers, even though
407 profiled, will appear to be spontaneous (although for more obscure
408 reasons). Any profiled children of signal catchers should have their
409 times propagated properly, unless the signal catcher was invoked during
410 the execution of the profiling routine, in which case all is lost.
411 The profiled program must call "exit"(2) or return normally for the
413 profiling information to be saved in the gmon.out file.
414
416 monitor(3), profil(2), cc(1), prof(1), and the Info entry for gprof.
417 "An Execution Profiler for Modular Programs", by S. Graham, P. Kessler,
419 M. McKusick; Software - Practice and Experience, Vol. 13, pp. 671-685,
420 1983.
421 "gprof: A Call Graph Execution Profiler", by S. Graham, P. Kessler, M.
423 McKusick; Proceedings of the SIGPLAN '82 Symposium on Compiler
424 Construction, SIGPLAN Notices, Vol. 17, No 6, pp. 120-126, June 1982.
425
427 Copyright (c) 1988-2023 Free Software Foundation, Inc.
428 Permission is granted to copy, distribute and/or modify this document
430 under the terms of the GNU Free Documentation License, Version 1.3 or
431 any later version published by the Free Software Foundation; with no
432 Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
433 Texts. A copy of the license is included in the section entitled "GNU
434 Free Documentation License".
435binutils-2.40.00 2023-01-14 GPROF(1)