Re: REINDEX : new parameter to preserve current average leaf density as new implicit FILLFACTOR

> From: Peter Geoghegan <pg(at)bowt(dot)ie>
> Sent: July 8, 2019 1:39 PM
> Subject: Re: REINDEX : new parameter to preserve current average leaf density as new implicit FILLFACTOR
>
> On Mon, Jul 8, 2019 at 9:23 AM John Lumby <johnlumby(at)hotmail(dot)com> wrote:
>
> > Although a welcome improvement, I think it is not enough to justify stopping use of setting
> > a lower explicit FILLFACTOR. Which then brings me back to thinking there is a case
> > for the subject of this thread, an automatic way to preserve density.
>
> I don't think that such an option would make much sense. The "waves of
> misery" paper is about smoothing out the frequency of page splits
> following bulk loading and a CREATE INDEX. It is not about making
> splits occur less often. It's well understood that a certain amount of
> free space is the overhead of B-Tree indexes, albeit an overhead that
> can be avoided in certain specific instances.
>
Yes, I see that. But surely "making splits occur less often" is a desirable
objective in itself, is it not? And I believe that a parameter to preserve the "steady-state"
density in high-traffic indexes would help achieve that goal, wouldn't you agree?

Cheers, John Lumby