Re: [boost] [boost thread rework] New version uploaded to BoostVault

From: Peter Dimov (pdimov_at_[hidden])
Date: 2005-09-02 12:35:40

Greer, Joe wrote:
>> -----Original Message-----
>> Running the test program, the semaphore version gives a timing of 16s
>> compiled
>> with gcc-mingw-4.0.1, and 22s compiled with MSVC 7.1, on my machine.
> The
>> mutex
>> version gives timings of 23s (gcc) and 29s (MSVC), so the semaphore
>> version is
>> clearly faster.
>> 
> 
> Why use either?  I wrote an implantation using critical sections and
> my timings are:
> 
> Semaphores: 20
> Mutex: 27
> Critical section: 0
> 
> I must be missing something vital.

You have a local static that is not thread-safe in general.