RE: [Boost-users] Re: shared_ptr: LWM versus atomic_count?

From: Ben Hutchings (ben.hutchings_at_[hidden])
Date: 2004-07-19 07:01:16

Russell Hind <rhind_at_[hidden]> wrote:
> Ben Hutchings wrote:
> > 
> > It isn't fundamentally necessary to have two counters, though; see
> > <http://groups.google.com/groups?threadm=slrnbhbnpc.154.do-not-spam
> > -benh%40tin.bwsint.com>.
> 
> I'd seen this (I think you posted the same link recently).  I don't
> know if anything has been done to change the implementation of
> shared_ptr to use this method, though (nothing to do with me).

The difficulty is that it depends on a couple of unportable atomic
functions that can't be implemented using the existing contents of
Boost.Threads or pthreads (though they do translate neatly into
Win32 functions).

> If the speed increases mentioned are correct, then it certinaly
> seems a good proposal.

Well maybe I'll have a go at implementing it properly and then trying
to get it into Boost.  I suppose it can be selectively enabled for
those platforms that support it.