DOC HOME SITE MAP MAN PAGES GNU INFO SEARCH PRINT BOOK
 

gprof(1)




GPROF(1)                       GNU                       GPROF(1)


NAME

     gprof - display call graph profile data


SYNOPSIS

     gprof [ -[abcDhilLrsTvwxyz] ] [ -[ACeEfFJnNOpPqQZ][name] ]
      [ -I dirs ] [ -d[num] ] [ -k from/to ]
      [ -m min-count ] [ -R map_file ] [ -t table-length ]
      [ --[no-]annotated-source[=name] ]
      [ --[no-]exec-counts[=name] ]
      [ --[no-]flat-profile[=name] ] [ --[no-]graph[=name] ]
      [ --[no-]time=name] [ --all-lines ] [ --brief ]
      [ --debug[=level] ] [ --function-ordering ]
      [ --file-ordering map_file ] [ --directory-path=dirs ]
      [ --display-unused-functions ] [ --file-format=name ]
      [ --file-info ] [ --help ] [ --line ] [ --inline-file-names
     ]
      [ --min-count=n ] [ --no-static ] [ --print-path ]
      [ --separate-files ] [ --static-call-graph ] [ --sum ]
      [ --table-length=len ] [ --traditional ] [ --version ]
      [ --width=n ] [ --ignore-non-functions ]
      [ --demangle[=STYLE] ] [ --no-demangle ]
      [--external-symbol-table=name]
      [ image-file ] [ profile-file ... ]


DESCRIPTION

     "gprof" 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 (gmon.out
     default) which is created by programs that are compiled with
     the -pg option of "cc", "pc", and "f77".  The -pg option
     also links in versions of the library routines that are
     compiled for profiling.  "Gprof" reads the given object file
     (the default is "a.out") and establishes the relation
     between its symbol table and the call graph profile from
     gmon.out.  If more than one profile file is specified, the
     "gprof" output shows the sum of the profile information in
     the given profile files.

     "Gprof" 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 cycle.

     Several forms of output are available from the analysis.

     The flat profile shows how much time your program spent in
     each function, and how many times that function was called.
     If you simply want to know which functions burn most of the
     cycles, it is stated concisely here.

binutils-2.30.0      Last change: 2018-01-13                    1

GPROF(1)                       GNU                       GPROF(1)

     The call graph shows, for each function, which functions
     called it, which other functions it called, and how many
     times.  There is also an estimate of how much time was spent
     in the subroutines of each function.  This can suggest
     places where you might try to eliminate function calls that
     use a lot of time.

     The annotated source listing is a copy of the program's
     source code, labeled with the number of times each line of
     the program was executed.


OPTIONS

     These options specify which of several output formats
     "gprof" should produce.

     Many of these options take an optional symspec to specify
     functions to be included or excluded.  These options can be
     specified multiple times, with different symspecs, to
     include or exclude sets of symbols.

     Specifying any of these options overrides the default (-p
     -q), which prints a flat profile and call graph analysis for
     all functions.

     "-A[symspec]"
     "--annotated-source[=symspec]"
         The -A option causes "gprof" to print annotated source
         code.  If symspec is specified, print output only for
         matching symbols.

     "-b"
     "--brief"
         If the -b option is given, "gprof" doesn't print the
         verbose blurbs that try to explain the meaning of all of
         the fields in the tables.  This is useful if you intend
         to print out the output, or are tired of seeing the
         blurbs.

     "-C[symspec]"
     "--exec-counts[=symspec]"
         The -C option causes "gprof" to print a tally of
         functions and the number of times each was called.  If
         symspec is specified, print tally only for matching
         symbols.

         If the profile data file contains basic-block count
         records, specifying the -l option, along with -C, will
         cause basic-block execution counts to be tallied and
         displayed.

     "-i"
     "--file-info"

binutils-2.30.0      Last change: 2018-01-13                    2

GPROF(1)                       GNU                       GPROF(1)

         The -i option causes "gprof" to display summary
         information about the profile data file(s) and then
         exit.  The number of histogram, call graph, and basic-
         block count records is displayed.

     "-I dirs"
     "--directory-path=dirs"
         The -I option specifies a list of search directories in
         which to find source files.  Environment variable
         GPROF_PATH can also be used to convey this information.
         Used mostly for annotated source output.

     "-J[symspec]"
     "--no-annotated-source[=symspec]"
         The -J option causes "gprof" not to print annotated
         source code.  If symspec is specified, "gprof" prints
         annotated source, but excludes matching symbols.

     "-L"
     "--print-path"
         Normally, source filenames are printed with the path
         component suppressed.  The -L option causes "gprof" to
         print the full pathname of source filenames, which is
         determined from symbolic debugging information in the
         image file and is relative to the directory in which the
         compiler was invoked.

     "-p[symspec]"
     "--flat-profile[=symspec]"
         The -p option causes "gprof" to print a flat profile.
         If symspec is specified, print flat profile only for
         matching symbols.

     "-P[symspec]"
     "--no-flat-profile[=symspec]"
         The -P option causes "gprof" to suppress printing a flat
         profile.  If symspec is specified, "gprof" prints a flat
         profile, but excludes matching symbols.

     "-q[symspec]"
     "--graph[=symspec]"
         The -q option causes "gprof" to print the call graph
         analysis.  If symspec is specified, print call graph
         only for matching symbols and their children.

     "-Q[symspec]"
     "--no-graph[=symspec]"
         The -Q option causes "gprof" to suppress printing the
         call graph.  If symspec is specified, "gprof" prints a
         call graph, but excludes matching symbols.

     "-t"

binutils-2.30.0      Last change: 2018-01-13                    3

GPROF(1)                       GNU                       GPROF(1)

     "--table-length=num"
         The -t option causes the num most active source lines in
         each source file to be listed when source annotation is
         enabled.  The default is 10.

     "-y"
     "--separate-files"
         This option affects annotated source output only.
         Normally, "gprof" prints annotated source files to
         standard-output.  If this option is specified, annotated
         source for a file named path/filename is generated in
         the file filename-ann.  If the underlying file system
         would truncate filename-ann so that it overwrites the
         original filename, "gprof" generates annotated source in
         the file filename.ann instead (if the original file name
         has an extension, that extension is replaced with .ann).

     "-Z[symspec]"
     "--no-exec-counts[=symspec]"
         The -Z option causes "gprof" not to print a tally of
         functions and the number of times each was called.  If
         symspec is specified, print tally, but exclude matching
         symbols.

     "-r"
     "--function-ordering"
         The --function-ordering option causes "gprof" to print a
         suggested function ordering for the program based on
         profiling data.  This option suggests an ordering which
         may improve paging, tlb and cache behavior for the
         program on systems which support arbitrary ordering of
         functions in an executable.

         The exact details of how to force the linker to place
         functions in a particular order is system dependent and
         out of the scope of this manual.

     "-R map_file"
     "--file-ordering map_file"
         The --file-ordering option causes "gprof" to print a
         suggested .o link line ordering for the program based on
         profiling data.  This option suggests an ordering which
         may improve paging, tlb and cache behavior for the
         program on systems which do not support arbitrary
         ordering of functions in an executable.

         Use of the -a argument is highly recommended with this
         option.

         The map_file argument is a pathname to a file which
         provides function name to object file mappings.  The
         format of the file is similar to the output of the

binutils-2.30.0      Last change: 2018-01-13                    4

GPROF(1)                       GNU                       GPROF(1)

         program "nm".

                 c-parse.o:00000000 T yyparse
                 c-parse.o:00000004 C yyerrflag
                 c-lang.o:00000000 T maybe_objc_method_name
                 c-lang.o:00000000 T print_lang_statistics
                 c-lang.o:00000000 T recognize_objc_keyword
                 c-decl.o:00000000 T print_lang_identifier
                 c-decl.o:00000000 T print_lang_type
                 ...

         To create a map_file with GNU "nm", type a command like
         "nm --extern-only --defined-only -v --print-file-name
         program-name".

     "-T"
     "--traditional"
         The -T option causes "gprof" to print its output in
         "traditional" BSD style.

     "-w width"
     "--width=width"
         Sets width of output lines to width.  Currently only
         used when printing the function index at the bottom of
         the call graph.

     "-x"
     "--all-lines"
         This option affects annotated source output only.  By
         default, only the lines at the beginning of a basic-
         block are annotated.  If this option is specified, every
         line in a basic-block is annotated by repeating the
         annotation for the first line.  This behavior is similar
         to "tcov"'s -a.

     "--demangle[=style]"
     "--no-demangle"
         These options control whether C++ symbol names should be
         demangled when printing output.  The default is to
         demangle symbols.  The "--no-demangle" option may be
         used to turn off demangling. Different compilers have
         different mangling styles.  The optional demangling
         style argument can be used to choose an appropriate
         demangling style for your compiler.

  Analysis Options
     "-a"
     "--no-static"
         The -a option causes "gprof" to suppress the printing of
         statically declared (private) functions.  (These are
         functions whose names are not listed as global, and
         which are not visible outside the file/function/block

binutils-2.30.0      Last change: 2018-01-13                    5

GPROF(1)                       GNU                       GPROF(1)

         where they were defined.)  Time spent in these
         functions, calls to/from them, etc., will all be
         attributed to the function that was loaded directly
         before it in the executable file.  This option affects
         both the flat profile and the call graph.

     "-c"
     "--static-call-graph"
         The -c option causes the call graph of the program to be
         augmented by a heuristic which examines the text space
         of the object file and identifies function calls in the
         binary machine code.  Since normal call graph records
         are only generated when functions are entered, this
         option identifies children that could have been called,
         but never were.  Calls to functions that were not
         compiled with profiling enabled are also identified, but
         only if symbol table entries are present for them.
         Calls to dynamic library routines are typically not
         found by this option.  Parents or children identified
         via this heuristic are indicated in the call graph with
         call counts of 0.

     "-D"
     "--ignore-non-functions"
         The -D option causes "gprof" to ignore symbols which are
         not known to be functions.  This option will give more
         accurate profile data on systems where it is supported
         (Solaris and HPUX for example).

     "-k from/to"
         The -k option allows you to delete from the call graph
         any arcs from symbols matching symspec from to those
         matching symspec to.

     "-l"
     "--line"
         The -l option enables line-by-line profiling, which
         causes histogram hits to be charged to individual source
         code lines, instead of functions.  This feature only
         works with programs compiled by older versions of the
         "gcc" compiler.  Newer versions of "gcc" are designed to
         work with the "gcov" tool instead.

         If the program was compiled with basic-block counting
         enabled, this option will also identify how many times
         each line of code was executed.  While line-by-line
         profiling can help isolate where in a large function a
         program is spending its time, it also significantly
         increases the running time of "gprof", and magnifies
         statistical inaccuracies.

     "--inline-file-names"

binutils-2.30.0      Last change: 2018-01-13                    6

GPROF(1)                       GNU                       GPROF(1)

         This option causes "gprof" to print the source file
         after each symbol in both the flat profile and the call
         graph. The full path to the file is printed if used with
         the -L option.

     "-m num"
     "--min-count=num"
         This option affects execution count output only.
         Symbols that are executed less than num times are
         suppressed.

     "-nsymspec"
     "--time=symspec"
         The -n option causes "gprof", in its call graph
         analysis, to only propagate times for symbols matching
         symspec.

     "-Nsymspec"
     "--no-time=symspec"
         The -n option causes "gprof", in its call graph
         analysis, not to propagate times for symbols matching
         symspec.

     "-Sfilename"
     "--external-symbol-table=filename"
         The -S option causes "gprof" to read an external symbol
         table file, such as /proc/kallsyms, rather than read the
         symbol table from the given object file (the default is
         "a.out"). This is useful for profiling kernel modules.

     "-z"
     "--display-unused-functions"
         If you give the -z option, "gprof" will mention all
         functions in the flat profile, even those that were
         never called, and that had no time spent in them.  This
         is useful in conjunction with the -c option for
         discovering which routines were never called.

  Miscellaneous Options
     "-d[num]"
     "--debug[=num]"
         The -d num option specifies debugging options.  If num
         is not specified, enable all debugging.

     "-h"
     "--help"
         The -h option prints command line usage.

     "-Oname"
     "--file-format=name"
         Selects the format of the profile data files.
         Recognized formats are auto (the default), bsd, 4.4bsd,

binutils-2.30.0      Last change: 2018-01-13                    7

GPROF(1)                       GNU                       GPROF(1)

         magic, and prof (not yet supported).

     "-s"
     "--sum"
         The -s option causes "gprof" to summarize the
         information in the profile data files it read in, and
         write out a profile data file called gmon.sum, which
         contains all the information from the profile data files
         that "gprof" read in.  The file gmon.sum may be one of
         the specified input files; the effect of this is to
         merge the data in the other input files into gmon.sum.

         Eventually you can run "gprof" again without -s to
         analyze the cumulative data in the file gmon.sum.

     "-v"
     "--version"
         The -v flag causes "gprof" to print the current version
         number, and then exit.

  Deprecated Options
     These options have been replaced with newer versions that
     use symspecs.

     "-e function_name"
         The -e function option tells "gprof" to not print
         information about the function function_name (and its
         children...) in the call graph.  The function will still
         be listed as a child of any functions that call it, but
         its index number will be shown as [not printed].  More
         than one -e option may be given; only one function_name
         may be indicated with each -e option.

     "-E function_name"
         The "-E function" option works like the "-e" option, but
         time spent in the function (and children who were not
         called from anywhere else), will not be used to compute
         the percentages-of-time for the call graph.  More than
         one -E option may be given; only one function_name may
         be indicated with each -E option.

     "-f function_name"
         The -f function option causes "gprof" to limit the call
         graph to the function function_name and its children
         (and their children...).  More than one -f option may be
         given; only one function_name may be indicated with each
         -f option.

     "-F function_name"
         The -F function option works like the "-f" option, but
         only time spent in the function and its children (and
         their children...) will be used to determine total-time

binutils-2.30.0      Last change: 2018-01-13                    8

GPROF(1)                       GNU                       GPROF(1)

         and percentages-of-time for the call graph.  More than
         one -F option may be given; only one function_name may
         be indicated with each -F option.  The -F option
         overrides the -E option.


FILES

     "a.out"
         the namelist and text space.

     "gmon.out"
         dynamic call graph and profile.

     "gmon.sum"
         summarized dynamic call graph and profile.


BUGS

     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 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 "exit"(2) or return normally
     for the profiling information to be saved in the gmon.out
     file.


SEE ALSO

     monitor(3), profil(2), cc(1), prof(1), and the Info entry
     for gprof.

     "An Execution Profiler for Modular Programs", by S. Graham,
     P. Kessler, M. McKusick; Software - Practice and Experience,
     Vol. 13, pp. 671-685, 1983.

     "gprof: A Call Graph Execution Profiler", by S. Graham, P.
     Kessler, M. McKusick; Proceedings of the SIGPLAN '82
     Symposium on Compiler Construction, SIGPLAN Notices, Vol.
     17, No  6, pp. 120-126, June 1982.

binutils-2.30.0      Last change: 2018-01-13                    9

GPROF(1)                       GNU                       GPROF(1)


COPYRIGHT

     Copyright (c) 1988-2018 Free Software Foundation, Inc.

     Permission is granted to copy, distribute and/or modify this
     document under the terms of the GNU Free Documentation
     License, Version 1.3 or any later version published by the
     Free Software Foundation; with no Invariant Sections, with
     no Front-Cover Texts, and with no Back-Cover Texts.  A copy
     of the license is included in the section entitled "GNU Free
     Documentation License".

binutils-2.30.0      Last change: 2018-01-13                   10


Man(1) output converted with man2html