Re: lwlocks and starvation

Neil, where are we on this?  Should we add comments?  Add a TODO?  A patch?

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Neil Conway wrote:
> On Wed, 2004-11-24 at 23:30 -0500, Tom Lane wrote:
> > It is not a 100% solution because it does not
> > cover the case where a waiting exclusive locker is released, then a new
> > shared locker arrives at the lock before the exclusive locker is given
> > any cycles to acquire the lock.  However I don't see any cure for the
> > latter problem that's not worse than the disease
> 
> Yeah, I don't think this is a problem -- eventually the exclusive waiter
> will win the coin flip anyway.
> 
> > On the other hand we might consider that this isn't a big problem and
> > just leave things as they are.  We haven't seen any indication that
> > starvation is a real problem in practice, and so it might be better to
> > avoid extra trips through the kernel scheduler.
> 
> Yes, I'm a little concerned about applying a patch to address what is,
> so far, an entirely academic concern -- especially if it might hurt
> performance.
> 
> -Neil
> 
> 

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