Date: Thu, 17 Feb 2022 16:18:22 -0800
From: Andres Freund <andres@anarazel.de>
To: Peter Geoghegan <pg@bowt.ie>
Cc: PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Subject: Re: Nonrandom scanned_pages distorts pg_class.reltuples set by VACUUM
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Hi,

On 2022-02-17 14:23:51 -0800, Peter Geoghegan wrote:
> On Thu, Feb 17, 2022 at 10:33 AM Andres Freund <andres@anarazel.de> wrote:
> > On 2022-02-16 19:43:09 -0800, Peter Geoghegan wrote:
> > > It makes the code in vacuumlazy.c much cleaner. In fact, that's how commit
> > > 44fa8488 started off -- purely as refactoring work.
> >
> > The problem is that it didn't end up as that. You combined refactoring with
> > substantial changes. And described it large and generic terms.
> 
> What substantial changes are you referring to? The one thing that did
> change was the commit message, which framed everything in terms of the
> later work. It really is true that the patch that I committed was
> essentially the same patch as the one posted on November 22, in both
> style and substance. Before I really even began to think about the
> freezing stuff. This is a matter of record.

Here I was referencing your description of how the patch started ("purely as
refactoring work"), and then evolved into something not just a refactoring.


> > It's a contentious thread. I asked for things to be split. In that context,
> > it's imo common curtesy for non-trivial patches to write something like
> 
> I didn't see a way to usefully split up 0001 any further (having
> already split it up into 0001 and 0002). That's not particularly
> obvious, but it's true.

If helpful I can give a go at showing how I think it could be split up. Or
perhaps more productively, do that on a not-yet-committed larger patch.

Greetings,

Andres Freund