gprof

GNU execution profiler

TLDR

Generate profile report

$ gprof [program] [gmon.out]

Flat profile only

$ gprof -p [program]

Call graph only

$ gprof -q [program]

Suppress static functions

$ gprof -a [program]

Output to file

$ gprof [program] > [profile.txt]

SYNOPSIS

gprof [options] [executable] [profile-data]

gprof analyzes program execution profiles to identify performance bottlenecks. It requires programs compiled with the -pg flag and produces reports showing time spent in each function and call relationships.The tool generates two main reports: a flat profile showing time per function, and a call graph showing function relationships and cumulative times.

PARAMETERS

-p, --flat-profile

Print flat profile only.

-q, --graph

Print call graph only.

-b, --brief

Suppress explanatory text.

-a, --no-static

Suppress static functions.

-z, --display-unused-functions

Show functions never called.

-c, --static-call-graph

Discover child functions by scanning the machine code, even if never called at runtime.

-A, --annotated-source

Print annotated source.

-l, --line

Line-by-line profiling.

-s, --sum

Accumulate several profile data files into a summary `gmon.sum`.

-i, --file-info

Print summary information about the profile data file, then exit.

WORKFLOW

$ # 1. Compile with profiling
gcc -pg -o program program.c

# 2. Run program (generates gmon.out)
./program

# 3. Analyze profile
gprof program gmon.out > analysis.txt

INSTALL

sudo apt install binutils

sudo dnf install binutils

sudo pacman -S binutils

sudo apk add binutils

sudo zypper install binutils

brew install binutils

nix profile install nixpkgs#binutils

CAVEATS

Requires recompilation with -pg. Adds overhead to execution. Sampling-based; short-running functions may be underrepresented. Modern alternatives include perf and valgrind.

HISTORY

gprof was developed at UC Berkeley in the early 1980s by Susan Graham, Peter Kessler, and Marshall McKusick. It became the standard Unix profiler and remains part of GNU binutils.