[Boost-build] bjam acceleration

From: Motonari Ito (motonarii_at_[hidden])
Date: 2007-10-25 01:14:05

Hi,

The biggest problem I have in bjam is its speed.

We have 1M lines of code managed by Boost Build system (V2). Bjam takes
20-30 second (when current directory is root) or 5-6 second (when
current directory is leaf) before starting actual compilations. It's
very slow for daily compile & edit development.

So, I have profiled on the latest bjam (Milestone 12) with Rational
Quantify. It looks like memory and hash related functions are bottle
neck - is there any chance to accelerate them?

[TOP-5 bottle neck by function time]

HeapAlloc  16.83 %  <- It's Win32 API
hashitem   10.72 %
var_expand  10.31 %
hash_search	8.89%
string_append 8.64%

The raw data is attached.

Thank you.