Re: Proposal of tunable fix for scalability of 8.4

Robert Haas wrote:
> > The original poster's request is for a config parameter, for experimentation
> > and testing by the brave. My own request was for that version of the lock to
> > prevent possible starvation but improve performance by unlocking all shared
> > at once, then doing all exclusives one at a time next, etc.
>
> That doesn't prevent starvation in general, although it will for some workloads.
>
> Anyway, it seems rather pointless to add a config parameter that isn't
> at all safe, and adds overhead to a critical part of the system for
> people who don't use it. After all, if you find that it helps, what
> are you going to do? Turn it on in production? I just don't see how
> this is any good other than as a thought-experiment.

We prefer things to be auto-tuned, and if not, it should be clear
how/when to set the configuration parameter.

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

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