Message-ID: <d1581404ad5169663d985d78262e948ff2877c51.camel@cybertec.at>
Subject: Re: Read-only connectios optimizatios
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Edson Richter <edsonrichter@hotmail.com>,
 "pgsql-performance@lists.postgresql.org"
	 <pgsql-performance@lists.postgresql.org>
Date: Sat, 25 Jan 2025 19:01:31 +0100
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On Sat, 2025-01-25 at 14:55 +0000, Edson Richter wrote:
> -Connections are established using the jdbc "readonly" attribute.
>=20
> Does PostgreSQL perform any optimization on queries in this scenario to a=
void
> establishing locks? Or are these queries treated like any other?

The only difference that I am aware of is that read-only transactions at th=
e
SERIALIZABLE isolation level can release predicate locks earlier, which can
benefit performance.

But I don't think that you need to worry: reading transactions only take an
ACCESS SHARE lock on tables, which won't conflict with data modifications.

Yours,
Laurenz Albe