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From: Alexander Terekhov <terekhov@web.de>
Newsgroups: comp.programming.threads
Subject: Re: usage of vyukov's mpsc queue
Date: Wed, 21 Sep 2011 18:20:13 +0200
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Ephi Sinowitz wrote:
> 
> On Sep 21, 11:06 am, Alexander Terekhov <terek...@web.de> wrote:
> > Ephi Sinowitz wrote:
> >
> > [...]
> >
> > > Producers set event after the push(). Event only transitions from
> > > unset to set when producer is inside the while loop.
> > > Now when Consumer goes back to Wait he should see the set event. The
> > > only issue is that he may still see a NULL next pointer because there
> > > are no memory barriers in the push(). In that case the consumer will
> > > go back to wait and the event will stay unset forever. But the 30
> > > second time limit should take care of that.
> > > for(;;)
> > >        WaitForSingleObject(m_queueEvent, 30000);
> > >         while (void* item = vyukov_queue.pop())
> > >         {
> > >             // do work
> > >         }
> > > }
> >
> > With *timed* wait on <whatever> in consumer, push() and pop() need the
> > same barriers as without <whatever> blocking synchronization object.
> >
> > Think of it as sleep(30) instead of WaitForSingleObject(m_queueEvent,
> > 30000).
> >
> > regards,
> > alexander.
> 
> But that's the point. This queue does not need any memory barriers if
> the consumer is just spinning with a sleep.

Who told you that, Ephi?

regards,
alexander.