Re: doc: BRIN indexes and autosummarize

On Mon, Jul 4, 2022 at 9:20 AM Alvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org>
wrote:

>
> [Some of] these additions are wrong actually. It says that autovacuum
> will not summarize new entries; but it does. If you just let the table
> sit idle, any autovacuum run that cleans the table will also summarize
> any ranges that need summarization.
>
> What 'autosummarization=off' means is that the behavior to trigger an
> immediate summarization of a range once it becomes full is not default.
> This is very different.
>

Without having read through the code, I'll take your word for it. I simply
went with what was written on this phrase of the docs:

"or by automatic summarization executed by autovacuum, as insertions occur.
(This last trigger is disabled by default and can be enabled with the
autosummarize parameter.)"

To me this did not indicate a third behavior, which is what you are
describing, so I'm glad we're having this discussion to clarify it.

As for the new <para></para>s that you added, I'd say they're
> stylistically wrong. Each paragraph is supposed to be one fully
> contained idea; what these tags do is split each idea across several
> smaller paragraphs. This is likely subjective though.
>

While I don't disagree with you, readability is more important. We have
lots of places (such as that one on the docs) where we have a big blob of
text, reducing readability, IMHO. In the source they are broken by new
lines, but in the rendered HTML, which is what the vast majority of people
read, they get rendered into a big blob-looking-thing.

> What would be the downside (if any) of having autosummarize=on by default?
>
> I'm not aware of any. Maybe we should turn it on by default.
>

+1

Thanks for looking at this Alvaro.

Roberto
--
Cunchy Data -- passion for open source PostgreSQL