Re: generic plans and "initial" pruning - Mailing list pgsql-hackers

From Thom Brown
Subject Re: generic plans and "initial" pruning
Date
Msg-id CAA-aLv5EDpYBaZrPjE_kkaoERQmAPHO=fm-FwDsw3xJG5gb8Lg@mail.gmail.com
Whole thread Raw
In response to Re: generic plans and "initial" pruning  (Amit Langote <amitlangote09@gmail.com>)
Responses Re: generic plans and "initial" pruning  (Amit Langote <amitlangote09@gmail.com>)
List pgsql-hackers
On Thu, 13 Jul 2023 at 13:59, Amit Langote <amitlangote09@gmail.com> wrote:
> In an absolutely brown-paper-bag moment, I realized that I had not
> updated src/backend/executor/README to reflect the changes to the
> executor's control flow that this patch makes.   That is, after
> scrapping the old design back in January whose details *were*
> reflected in the patches before that redesign.
>
> Anyway, the attached fixes that.
>
> Tom, do you think you have bandwidth in the near future to give this
> another look?  I think I've addressed the comments that you had given
> back in April, though as mentioned in the previous message, there may
> still be some funny-looking aspects still remaining.  In any case, I
> have no intention of pressing ahead with the patch without another
> committer having had a chance to sign off on it.

I've only just started taking a look at this, and my first test drive
yields very impressive results:

8192 partitions (3 runs, 10000 rows)
Head 391.294989 382.622481 379.252236
Patched 13088.145995 13406.135531 13431.828051

Looking at your changes to README, I would like to suggest rewording
the following:

+table during planning.  This means that inheritance child tables, which are
+added to the query's range table during planning, if they are present in a
+cached plan tree would not have been locked.

To:

This means that inheritance child tables present in a cached plan
tree, which are added to the query's range table during planning,
would not have been locked.

Also, further down:

s/intiatialize/initialize/

I'll carry on taking a closer look and see if I can break it.

Thom



pgsql-hackers by date:

Previous
From: Alvaro Herrera
Date:
Subject: Re: Looking for context around which event triggers are permitted
Next
From: Andres Freund
Date:
Subject: Report distinct wait events when waiting for WAL "operation"