pthread_mutex in a winelib dll called from a win32 application

[Mike Hearn]

On Wed, 21 Jul 2004 13:08:57 +0300, Shachar Shemesh wrote:
> Are there any restrictions in synchronizing wine generated threads 
> (generated through the win32 api) using the pthreads library native calls?

On NPTL (pthread) systems I think this should work. On kthread systems
pthreads is emulated by Wine anyway so you'd gain nothing.
 
> I have an app that is experiencing extremely slow performance (operation
> takes 17 seconds on native windows, over 3 minutes on Wine). One idea
> for solving this problem was to switch some of the synchronization
> operations over to native pthreads (it's using wine as part of a
> migration to Linux process).

Do you know for sure it's the synchro primitives that are causing the
slowdown?

> The problem is that when I try to call pthread_mutex_init,
> pthread_mutex_lock and friends, I get quite a few deadlocks, and even
> when not deadlocking, it still takes over 42 seconds. When doing the
> same without the mutexes (I'm locking write access to a pipe - I'm not
> sure it's even necessary, and it is working without the lock too), wine
> performs at 21-26 seconds. I don't think that obtaining a posix mutex
> should have such harsh effect on performance.

What kind of mutex are you using? Critical sections should only RPC to the
wineserver (which is the slow bit) when contended, iirc ... 
every time you block this involves a wineserver RPC so with high lock
contention that could be a problem.

thanks -mike