Re: max_prepared_transactions default ... why 5?

Josh Berkus wrote:
> On Wednesday 17 October 2007 21:35, Tom Lane wrote:
> > Josh Berkus <josh(at)agliodbs(dot)com> writes:
> > > I'm writing up the new GUCs, and noticed that max_prepared_transactions
> > > defaults to 5. This is too many for most applications (which don't use
> > > them at all) and far too few for applications which use them regularly.
> >
> > I think the intention was to have enough so you could test 'em (in
> > particular, run the regression tests) without eating resources for
> > the majority of installations that aren't using them.
> >
> > Certainly an installation that *is* using 'em would want a higher
> > setting.
>
> Yeah, given the amount of memory per xact, I guess we can't actually set the
> default higher. I just hate to see a setting that is liable to bite someone
> on the tuchas so easily.

They will see the failure at 5 faster and adjust it accordingly. If it
was higher they might hit the limit only under heavy load and it would
surprise them.

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

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