Re: lwlocks and starvation

Neil Conway wrote:
> Bruce Momjian wrote:
> > My guess is the existing behavior was designed to allow waking of
> > multiple waiters _sometimes_ without starving of exclusive waiters.
> 
> Well, I think the current algorithm *does* allow starvation, at least in 
> some situations. Consider a workload in which a new shared reader 
> arrives every 50 ms, and holds the lock for, say, 500 ms. If an 
> exclusive waiter arrives, they will starve with the current algorithm.

I thought the new readers will sit after the writer in the FIFO queue so
the writer will not starve.

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