Re: [boost] Mutexes claim a Windows event handle

Subject: Re: [boost] Mutexes claim a Windows event handle
From: Christian Holmquist (c.holmquist_at_[hidden])
Date: 2010-05-31 12:44:38

> I tried the latest Boost version (1.43) but that makes no difference.
> The strange thing is that not every object keeps a handle, i.e.: the
> number of handles collected is less than the number of objects created.
> When increasing the nrActions the number of handles collected comes
> closer to the number of objects.
>
> I could understand if a recursive_mutex costs a handle, except that in
> boost 1.34 they didn't so I wonder if this was an accident or a
> deliberate change. And most important: Is there a way to get the same
> behavior as in 1.34 where a mutex did not cost me one handle each?
>
>
>

Typically implementations lazily create the Event object when the mutex
cannot be aquired. I guess that Boost Thread's implementation is doing this
in the same fashion as Window's CRITICAL_SECTION.

I don't have Boost 1.34 around, but I would be surprised if there never was
an Event object related to the mutex.. Have nothing else changed in your
application, that increases the chance of thread contention?

/ Christian