Re: [Monotone-devel] more profiling

[Nathaniel Smith]

On Sun, Apr 17, 2005 at 09:31:27PM +0200, Sebastian Spaeth wrote:
> Now,a callgraph would be interesting, don't ask me how to get one though

Pass --callgraph=<number> to opcontrol.  The number determines how
deep in the callgraph oprofile will save; higher is better but uses
more space.  8-10 should be fine to start, but probably worth
experimenting with.

Make sure to build debugging (or at least unstripped) versions of your
binary and your libraries.  Don't use -fomit-frame-pointer.  I used to
recommend installing -dbg versions of libraries if your system has
them (e.g., apt-get install libboost-dbg libc6-dbg), but now I'm
nervous that those aren't compiled with optimization, which will screw
up your profiles; probably best to build them by hand.  (This whole
paragraph applies equally to callgraph and non-callgraph profiling,
actually.)

Run your program under the profile as usual (opcontrol --start and all
that).

Now opstack <path to binary> gives you lots of yummy data, that takes
a little squinting to start interpreting:
  http://oprofile.sourceforge.net/doc/opstack.html

-- Nathaniel

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