| |
| # Note that you must do all the following as root (I believe). |
| # Although the program to be profiled can be run by anybody. |
| |
| # start the profiler |
| opcontrol --stop ; opcontrol --reset ; opcontrol --callgraph=5 --start |
| |
| # now run the program(s) to be profiled |
| |
| # stop the profiler and dump results to .. um .. some file somewhere |
| opcontrol --stop ; opcontrol --dump |
| |
| # get total cost |
| opreport --merge=tgid -x \ |
| /home/sewardj/VgTRUNK/atomk/Inst/lib/valgrind/helgrind-amd64-linux \ |
| | less |
| |
| # produce a flat profile |
| opreport --merge=tgid --symbols -x \ |
| /home/sewardj/VgTRUNK/atomk/Inst/lib/valgrind/helgrind-amd64-linux \ |
| | less |
| |
| # produce a profile w/ callgraph |
| opreport --merge=tgid --callgraph -x \ |
| /home/sewardj/VgTRUNK/atomk/Inst/lib/valgrind/helgrind-amd64-linux \ |
| | less |
| |
| # print annotated source |
| opannotate --merge=tgid --source --include-file=libhb_core.c | less |
| |
| |
| #### notes. |
| |
| 1. on amd64, need to build V with -fno-omit-frame-pointer, else the |
| w/ callgraph profiles are useless. (oprofile doesn't do CFI based |
| stack unwinding, I guess). Add -fno-omit-frame-pointer to |
| AM_CFLAGS_BASE in Makefile.flags.am, and rebuild from clean. |
| |
| 2. even at the best of times the callgraph profiles seem pretty |
| flaky to me. |
| |
| 3. Even oprofile 0.9.4 (the latest) on amd64-linux doesn't work |
| for callgraph profiling. There is however a patch that |
| makes it work. See |
| |
| http://sourceforge.net/tracker/index.php?func=detail&aid=1685267&group_id=16191&atid=116191 |
| |
| for details. Even then it sometimes fails at the "opcontrol |
| --dump" phase, complaining that the daemon died (or something like |
| that). But apart from that, it seems usable. |
