Performance profiling on Linux

Question

What are the best tools for profiling C/C++ applications on *nix?

(I\'m hoping to profile a server that is a mix of (blocking) file IO, epoll for network and fork()/

Answer 1

Compile with -pg, run the program, and then use gprof

Compiling (and linking) with -pg adds profiling code and the profiling libraries to the executable, which then produces a file called gmon.out that contains the timing information. gprof displays call graphs and their (absolute and relative) timings.

See man gprof for details.

Answer 2

oprofile might interest you. Ubuntu should have all the packages you need.

Answer 3

Description of using -gp and gproff here http://www.ibm.com/developerworks/library/l-gnuprof.html

Answer 4

For performance, you can try Callgrind, a Valgrind tool. Here is a nice article showing it in action.