Re: Switch to multi-inserts for pg_depend

On 2020-Aug-11, Robert Haas wrote:

> On Tue, Aug 11, 2020 at 1:59 AM Michael Paquier <michael(at)paquier(dot)xyz> wrote:
> > On Mon, Aug 10, 2020 at 05:32:21PM -0700, Andres Freund wrote:
> > > Do we really want to end up with several separate defines for different
> > > type of catalog batch inserts? That doesn't seem like a good
> > > thing. Think there should be a single define for all catalog bulk
> > > inserts.
> >
> > Unlikely so, but I kept them separate to potentially lower the
> > threshold of 64kB for catalog rows that have a lower average size than
> > pg_attribute.
>
> Uh, why would we want to do that?

Yeah. As I understand, the only reason to have this number is to avoid
an arbitrarily large number of entries created as a single multi-insert
WAL record ... but does that really ever happen? I guess if you create
a table with some really complicated schema you might get, say, a
hundred pg_depend rows at once. But to fill eight complete pages of
pg_depend entries sounds astoundingly ridiculous already -- I'd say it's
just an easy way to spell "infinity" for this. Tweaking one infinity
value to become some other infinity value sounds useless.

So I agree with what Andres said. Let's have just one such define and
be done with it.

--
Álvaro Herrera https://www.2ndQuadrant.com/
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