id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
712	Regex: multi-processor scalability, user-defined allocators	r_emek	John Maddock	"{{{
I'm using boost-regex library, and I'm running into
multi-threading scalability issues. When tested on a
machine with several CPUs, my performance tests show
improvement of about 60-70% when moving from a single
thread to 2 threads. 

Question 1: Is anyone aware of this problem? Is there a
known solution?

From some testing we've done, it seems that the cause
of the scalability issue is problematic implementation
of std:allocator. This is a known issue on some
operating systems (e.g., Solaris 8). Some of the
boost::regex classes (e.g., match_results) accept a
user-defined allocator. However, as far as I can
understand there's no way to completely override the
use of std::allocator. 

Question 2: is there a way to completely prevent boost
/ regex from using std::allocator? If no, can such a
capability be added?

(One solution to this problem would be global
overriding the 'new' and 'delete' operators - but for
various reasons this cannot be done in the application
I'm developing). 
}}}"	Support Requests	closed		regex	None		None