Subject: Re: Overhauling "Routine Vacuuming" docs, particularly its handling of freezing

From: John Naylor <[email-masked]>
Date: Tue, 2 May 2023 10:04:40 +0700

On Tue, May 2, 2023 at 12:09 AM Peter Geoghegan <[email-masked]> wrote:
>
> On Mon, May 1, 2023 at 9:16 AM Peter Geoghegan <[email-masked]> wrote:
> > On Mon, May 1, 2023 at 9:08 AM Robert Haas <[email-masked]>
wrote:
> > > I disagree. If you start the cluster in single-user mode, you can
> > > actually wrap it around, unless something has changed that I don't
> > > know about.

+1 Pretending otherwise is dishonest.

> > This patch relies on John's other patch which strongly discourages the
> > use of single-user mode. Were it not for that, I might agree.

Oh that's rich. I'll note that 5% of your review was actually helpful
(actual correction), the other 95% was needless distraction trying to
enlist me in your holy crusade against the term "wraparound". It had the
opposite effect.

> Also, it's not clear that the term "wraparound" even describes what
> happens when you corrupt the database by violating the "no more than
> ~2.1 billion XIDs distance between any two unfrozen XIDs" invariant in
> single-user mode. What specific thing will have wrapped around?

In your first message you said "I'm hoping that I don't get too much push
back on this, because it's already very difficult work."

Here's some advice on how to avoid pushback:

1. Insist that all terms can only be interpreted in the most pig-headedly
literal sense possible.
2. Use that premise to pretend basic facts are a complete mystery.
3. Claim that others are holding you back, and then try to move the
goalposts in their work.

--
John Naylor
EDB: http://www.enterprisedb.com

---

From: Peter Geoghegan <[email-masked]>
Date: Mon, 1 May 2023 20:20:42 -0700

On Mon, May 1, 2023 at 8:04 PM John Naylor <[email-masked]> wrote:
> 1. Insist that all terms can only be interpreted in the most pig-headedly literal sense possible.

I can't imagine why you feel it necessary to communicate with me like
this. This is just vitriol, lacking any substance.

How we use words like wraparound is actually something of great
consequence to the Postgres project. We've needlessly scared users
with the way this information has been presented up until now -- that
much is clear. To have you talk to me like this when I'm working on
such a difficult, thankless task is a real slap in the face.

> 3. Claim that others are holding you back, and then try to move the goalposts in their work.

When did I say that? When did I even suggest it?

-- 
Peter Geoghegan

---

From: Peter Geoghegan <[email-masked]>
Date: Mon, 1 May 2023 21:19:11 -0700

On Mon, May 1, 2023 at 8:04 PM John Naylor <[email-masked]> wrote:
> Oh that's rich. I'll note that 5% of your review was actually helpful (actual correction), the other 95% was needless distraction trying to enlist me in your holy crusade against the term "wraparound". It had the opposite effect.

I went back and checked. There were exactly two short paragraphs about
wraparound terminology on the thread associated with the patch you're
working on, towards the end of this one email:

https://postgr.es/m/CAH2-Wzm2fpPQ_=[email-masked]

In what world does that amount to 95% of my review, or anything like it?

--
Peter Geoghegan

---

From: Robert Haas <[email-masked]>
Date: Tue, 2 May 2023 16:29:45 -0400

> this. This is just vitriol, lacking any substance.

John's email is pretty harsh, but I can understand why he's frustrated.

I told you that I did not agree with your dislike for the term
wraparound and I explained why. You sent a couple more emails telling
me that I was wrong and, frankly, saying a lot of things that seem
only tangentially related to the point that I was actually making. You
seem to expect other people to spend a LOT OF TIME trying to
understand what you're trying to say, but you don't seem to invest
similar effort in trying to understand what they're trying to say. I
couldn't even begin to grasp what your point was until Maciek stepped
in to explain, and I still don't really agree with it, and I expect
that no matter how many emails I write about that, your position won't
budge an iota.

It's really demoralizing. If I just vote -1 on the patch set, then I'm
a useless obstruction. If I actually try to review it, we'll exchange
100 emails and I won't get anything else done for the next two weeks
and I probably won't feel much better about the patch at the end of
that process than at the beginning. I don't see that I have any
winning options here.

-- 
Robert Haas

---

From: Peter Geoghegan <[email-masked]>
Date: Tue, 2 May 2023 14:00:41 -0700

On Tue, May 2, 2023 at 1:29 PM Robert Haas <[email-masked]> wrote:
> only tangentially related to the point that I was actually making.

I agree that that's what I did. You're perfectly entitled to find that
annoying (though I maintain that my point about the 64-bit XID space
was a good one, assuming the general subject matter was of interest).
However, you're talking about this as if I dug my feet in on a
substantive issue affecting the basic shape of the patch -- I don't
believe that that conclusion is justified by anything I've said or
done. I'm not even sure that we disagree on some less important point
that will directly affect the patch (it's quite possible, but I'm not
even sure of it).

I've already said that I don't think that the term wraparound is going
anywhere anytime soon (granted, that was on the other thread). So it's
not like I'm attempting to banish all existing use of that terminology
within the scope of this patch series -- far from it. At most I tried
to avoid inventing new terms that contain the word "wraparound" (also
on the other thread).

The topic originally came up in the context of moving talk about
physical wraparound to an entirely different chapter. Which is, I
believe (based in part on previous discussions), something that all
three of us already agree on! So again, I must ask: is there actually
a substantive disagreement at all?

> that process than at the beginning. I don't see that I have any

I've already put a huge amount of work into this. It is inherently a
very difficult thing to get right -- it's not hard to understand why
it was put off for so long. Why shouldn't I have opinions, given all
that? I'm frustrated too.

Despite all this, John basically agreed with my high level direction
-- all of the important points seemed to have been settled without any
arguments whatsoever (also based in part on previous discussions).
John's volley of abuse seemed to come from nowhere at all.

-- 
Peter Geoghegan