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Date: Wed, 10 Feb 2010 16:12:21 -0800
From: Alfred Perlstein <alfred@freebsd.org>
To: Daniel Eischen <eischen@vigrid.com>
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Cc: Daniel Eischen <deischen@freebsd.org>,
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Subject: Re: Thinking about kqueue's and pthread_cond_wait
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* Daniel Eischen <eischen@vigrid.com> [100210 16:11] wrote:
> On Feb 10, 2010, at 3:06 PM, Alfred Perlstein <alfred@freebsd.org>  
> wrote:
> 
> >* Daniel Eischen <deischen@freebsd.org> [100210 12:01] wrote:
> >>
> >>
> >>I strongly disagree.  Using mutexes and condition variables in the
> >>proper way is not as easy as it sounds, let alone trying to mix
> >>them as userland thingies into kqueue.
> >>
> >>I will strongly oppose this...
> >
> >Well then you "win".  I have no desire to engage in such discussion.
> >
> >I do hope that when you see this facility leveraged elsewhere for
> >an application that you reflect on this conversation and think back
> >on it the next time an opportunity presents itself to lead in
> >functionality.
> 
> Don't misunderstand me, I just don't think running around the tree and  
> adapting all the userland leaves to kqueue-isize them is the right  
> approach.  IMHO, it's better to extend the kqueue/kevent mechanism to  
> allow a generic object to be added to the event list and the kqueue to  
> be signaled from userland.  All the pthread and semaphore functions  
> are userland operations that also rely on userland structures anyway.

If you can show Randall a way to do this that will serve for his
proposed purpose then we might have a win here.
 

-- 
- Alfred Perlstein
.- AMA, VMOA #5191, 03 vmax, 92 gs500, 85 ch250
.- FreeBSD committer