[boost] Re: Boost.Threads: Do we need all those mutexes?

From: Howard Hinnant (hinnant_at_[hidden])
Date: 2004-07-08 08:45:52

On Jul 8, 2004, at 12:25 AM, Michael Glassford wrote:

> Howard Hinnant wrote:
>
> [big snip]
>
>> The downside to all this is that the sizeof(rw_mutex) about doubled 
>> to support upgradable_read_lock (whether or not you use that 
>> functionality).
>
> Really? (Not having tried to implement it,) that surprises me. Can you 
> give a few more details about why? I'm interested.

I had implemented rw_mutex with some conditions and integral types.  In 
adding upgradable_read support I doubled the number of both.  Sorry to 
be vague, but I'm only prepared to open source the interface.  
Metrowerks is selling the implementation for profit (or may in the 
future anyway).  I'm interested in open sourcing the interface because 
I would like to see this or a similar library standardized in C++0X.  
Dinkumware also sells a boost-derived threads lib.  So between boost 
and two commercial vendors for field experience, I think a standardized 
interface is a reasonable possibility for C++0X.  Just need to gather 
consensus and get that proposal written... :-)

-Howard