Re: [Boost-build] testing, profiling and bjam

From: Vladimir Prus (ghost_at_[hidden])
Date: 2007-08-03 05:49:18

Robert Ramey wrote:

> For sometime I've wanted to subject the serialization library to execution
> time profiing.  In the past I have spent significant time in program
> runtime optimization and have found such profiling indispensible.
> 
> So I built the serialization tests with
> 
> bjam --dump_tests --toolset=gcc-3.3 variant=profile ...
> 
> Hoping against hope that I would endup with a profile output in each test
> directory.
> 
> Well, my hopes weren't realized as I'm aware there there hasn't been much
> interest in this area.
> 
> However, good news was that the executables were built with the proper
> options and when run generated the required gmon.out file.
> 
> Bad news is the following:

The bad news is that gmon.out is useless. You won't get anyway accurate
information for any C++ library, and you'll end up with 
vector<something>::operator[] on top, or some such function.

> But I wonder is there some bjam magic which can be helpful with this
> process?  

The right solution is to run binaries under callgrind, and store
the output. This is not supported -- you're the first one to ask.
Note also that profiling the testsuite is not particularly good idea,
as testsuite are not likely to represent real-world data.

- Volodya