From: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
To: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Bruce Momjian <bruce@momjian.us>
Cc: Michael Paquier <michael@paquier.xyz>
Cc: Andres Freund <andres@anarazel.de>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: transction_timestamp() inside of procedures
Date: Wed, 26 Sep 2018 23:48:00 +0200
Message-ID: <ec816bd0-0357-23a9-bea2-3ef1619eb340@2ndquadrant.com> (raw)
In-Reply-To: <20180926155443.u4zh7jactzflys3z@alvherre.pgsql>
References: <20180926155443.u4zh7jactzflys3z@alvherre.pgsql>
On 26/09/2018 17:54, Alvaro Herrera wrote:
> What could be the use for the transaction timestamp? I think one of the
> most important uses (at least in pg_stat_activity) is to verify that
> transactions are not taking excessively long time to complete; that's
> known to cause all sorts of trouble in Postgres, and probably other
> DBMSs too. If we don't accurately measure what it really is, and
> instead keep the compatibility behavior, we risk panicking people
> because they think some transaction has been running for a long time
> when in reality it's just a very long procedure which commits frequently
> enough not to be a problem.
That's certainly a good argument. Note that if we implemented that the
transaction timestamp is advanced inside procedures, that would also
mean that the transaction timestamp as observed in pg_stat_activity
would move during VACUUM, for example. That might or might not be
desirable.
--
Peter Eisentraut http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
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: peter.eisentraut@2ndquadrant.com, alvherre@2ndquadrant.com, tgl@sss.pgh.pa.us, bruce@momjian.us, michael@paquier.xyz, andres@anarazel.de
Subject: Re: transction_timestamp() inside of procedures
In-Reply-To: <ec816bd0-0357-23a9-bea2-3ef1619eb340@2ndquadrant.com>
* 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