Profiling with Callgrind

Callgrind is a profiling tool that can be used via the Valgrind framework and its report can be displayed/inspected with the KCachegrind profile data visualization tool.

When you use Callgrind to profile a program, the program is transformed into an intermediate format and then is run in a virtual processor emulated by valgrind. That makes possible to keep track of operations and that makes the program run much more slower than otherwise.

Install

sudo apt-get install valgrind kcachegrind graphviz

Prepare

Not necessarily required but useful to have the debugging information in the binary so if it’s possible compile with the -g option.

gcc -g -o program program.c

Profile

# check options
man valgrind

# profile
valgrind --tool=callgrind <program> [program-options]

# profile with additional options e.g.
valgrind --tool=callgrind --dump-instr=yes --simulate-cache=yes --collect-jumps=yes <program> [program-options]

For more details on Callgrind’s features and way of working, it’s worth checking out its site.

Inspect

KCahcegrind is a graphical program and its interface is quite self-explanatory. If it is run from the directory where Callgrind just stored its reports into, it opens those by default.

kcachegrind &