Re: Proposal of tunable fix for scalability of 8.4

Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> I think that changing the locking behavior is attacking the problem
>> at the wrong level anyway.
>
> Right.  By the time a patch here could have any effect, you've
> already lost the game --- having to deschedule and reschedule a
> process is a large cost compared to the typical lock hold time for
> most LWLocks.  So it would be better to look at how to avoid
> blocking in the first place.

That's what motivated my request for a profile of the "80 clients with
zero wait" case.  If all data access is in RAM, why can't 80 processes
keep 64 threads (on 8 processors) busy?  Does anybody else think
that's an interesting question, or am I off in left field here?

-Kevin