pg.ddx.io  pgsql-hackers@postgresql.org mailing list archive  

help / color / mirror / Atom feed
From: Michael Paquier <michael@paquier.xyz>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Andres Freund <andres@anarazel.de>
Cc: Dilip Kumar <dilipbalaut@gmail.com>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Cc: Robert Haas <robertmhaas@gmail.com>
Subject: Re: Move pg_attribute.attcompression to earlier in struct for reduced size?
Date: Thu, 27 May 2021 10:00:16 +0900
Message-ID: <YK7vIBv+DDaQuebf@paquier.xyz> (raw)
In-Reply-To: <1677691.1622075746@sss.pgh.pa.us>
References: <YKdT5ZM5OInCsDkM@paquier.xyz>
	<3962395.1621609263@sss.pgh.pa.us>
	<20210521211929.pcehg6f23icwstdb@alap3.anarazel.de>
	<YKsm7qkz+Cq3C3mr@paquier.xyz>
	<CAFiTN-uLQCRLatapZhEaNGH9njY=LndyXJux7H9YCfT9RcE7gA@mail.gmail.com>
	<YKtpZI4PBpVG3ryH@paquier.xyz>
	<CAFiTN-vpHrCzdeyKxpoPViyJCZZx-h8KghQJFyxZd7+Dys6Cow@mail.gmail.com>
	<YKyPM6UC+tBHEuxo@paquier.xyz>
	<20210527003144.xxqppojoiwurc2iz@alap3.anarazel.de>
	<1677691.1622075746@sss.pgh.pa.us>

On Wed, May 26, 2021 at 08:35:46PM -0400, Tom Lane wrote:
> Andres Freund <andres@anarazel.de> writes:
> > The efficiency bit is probably going to be swamped by the addition of
> > the compression handling, given the amount of additional work we're now
> > doing in in reform_and_rewrite_tuple().
> 
> Only if the user has explicitly requested a change of compression, no?

Andres' point is that we'd still initialize and run through
values_free at the end of reform_and_rewrite_tuple() for each tuple
even if there no need to do so.  Well, we could control the
initialization and the free() checks at the end of the routine if we
know that there has been at least one detoasted value, at the expense
of making the code a bit less clear, of course.
--
Michael

Attachments:

  signature.asc (application/pgp-signature, 832B) download

view thread (73+ messages)  latest in thread

Message-ID: <YK7vIBv+DDaQuebf@paquier.xyz>
Permalink:  ../YK7vIBv+DDaQuebf@paquier.xyz/
Also on:    postgresql.org/message-id/YK7vIBv+DDaQuebf@paquier.xyz

 · 

reply
Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: pgsql-hackers@postgresql.org
  Cc: michael@paquier.xyz, tgl@sss.pgh.pa.us, andres@anarazel.de, dilipbalaut@gmail.com, robertmhaas@gmail.com
  Subject: Re: Move pg_attribute.attcompression to earlier in struct for reduced size?
  In-Reply-To: <YK7vIBv+DDaQuebf@paquier.xyz>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox