Horton

Re: Proposals for EXPLAIN: rename ANALYZE to EXECUTE and extend VERBOSE

Greg Sabino Mullane <htamfids@gmail.com>

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From: Greg Sabino Mullane <htamfids@gmail.com>
To: Guillaume Lelarge <guillaume@lelarge.info>
Cc: Robert Haas <robertmhaas@gmail.com>, Michael Christofides <michael@pgmustard.com>, David Rowley <dgrowleyml@gmail.com>, "David G. Johnston" <david.g.johnston@gmail.com>, Nikolay Samokhvalov <samokhvalov@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, pgsql-hackers@postgresql.org
Date: 2024-11-20T15:50:36Z
Lists: pgsql-hackers 
On Wed, Nov 20, 2024 at 1:26 AM Guillaume Lelarge <guillaume@lelarge.info>
wrote:

> OK, but I'm not sure which example I should pick to add dirtied and
> written shared buffers. It looks kinda artificial. Should I choose one
> randomly?
>

It will be artificial, but I think that's ok: anyone running it on their
own will be getting different numbers anyway. I was looking at the "14.1.2
EXPLAIN ANALYZE" section in perform.sgml. Here's some actual numbers I got
with some playing around with concurrent updates:

         Recheck Cond: (unique1 < 10)
>          Heap Blocks: exact=5
>          Buffers: shared hit=2 read=5 written=4

...

>  Planning:
>    Buffers: shared hit=289 dirtied=9


Cheers,
Greg

Commits

  1. Fix further fallout from EXPLAIN ANALYZE BUFFERS change

  2. Add missing BUFFERS OFF in regression tests, take 2

  3. Add missing BUFFERS OFF in select_into regression tests

  4. Enable BUFFERS with EXPLAIN ANALYZE by default