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Date: Fri, 14 Mar 2008 13:42:54 +0100
From: Corinna Vinschen <corinna-cygwin AT cygwin DOT com>
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Subject: Re: Re: pthread_mutex_lock/unlock performance?
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On Mar 14 12:47, Mojmir Svoboda wrote:
> morning, Corinna
> 
> > > the thing is that cygwin's pthread_mutex_lock performs quite lazily it
> > > takes about seven times more than using native critical section.
> 
> > Bookkeeping overhead? 
> 
> excuse my unfamiliarity with the matter, but i have no exact idea what
> bookkeping could be. could you elaborate the answer more, please?
> or point me to some article/documentation where i can read more?

Only in the source, sorry.  I'm also not exaclty familiar with the
pthread code in Cygwin.  I only look into it when a serious problem
crops up.

> > Just have a look into the Cygwin source.
> 
> yes, that's first place i tried to look, but got little disoriented
> with the _ and __ versions of the pthread_mutex_lock. i've eventually
> finished in __pthread_lock. am i on the right track?

Er... probably.

> > If you want to speed up Cygwin's pthread implementation, feel free to
> > contribute:  http://cygwin.com/contrib.html
> 
> well i'm using windows and cygwin for few months so i quite don't feel 
> ready... yet ;)

No worries.  Everyone of us started with moaning and hair pulling over
the existing code ;)


Corinna

-- 
Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

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