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

help / color / mirror / Atom feed
From: Anna Akenteva <a.akenteva@postgrespro.ru>
To: Andres Freund <andres@anarazel.de>
Cc: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Fujii Masao <masao.fujii@oss.nttdata.com>
Cc: Alexey Kondratov <a.kondratov@postgrespro.ru>
Cc: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Cc: a.korotkov@postgrespro.ru
Cc: i.kartyshov@postgrespro.ru
Cc: amit.kapila16@gmail.com
Cc: pgsql-hackers@lists.postgresql.org
Subject: Re: [HACKERS] make async slave to wait for lsn to be replayed
Date: Tue, 14 Apr 2020 12:52:07 +0300
Message-ID: <b797f7c14fd5e1227bb05fd964831465@postgrespro.ru> (raw)
In-Reply-To: <20200410214410.vzu6at6qbjq4yage@alap3.anarazel.de>
References: <13716.1586378146@sss.pgh.pa.us>
	<20200409.161107.580344062273684114.horikyota.ntt@gmail.com>
	<880834ee-4b18-6d5d-9dae-6520c5eb2bef@oss.nttdata.com>
	<27171.1586439221@sss.pgh.pa.us>
	<a8bff0350a27e0a87a6eaf0905d6737f@postgrespro.ru>
	<759206c1-265f-97da-d135-fcecbced646b@oss.nttdata.com>
	<20200410193301.2qsbuoieppkst7xj@alap3.anarazel.de>
	<32218.1586550579@sss.pgh.pa.us>
	<20200410210641.5cub2minmnciydvv@alap3.anarazel.de>
	<2024.1586553430@sss.pgh.pa.us>
	<20200410214410.vzu6at6qbjq4yage@alap3.anarazel.de>

On 2020-04-11 00:44, Andres Freund wrote:
> I think there's also some advantages of having it in a single statement
> for poolers. If a pooler analyzes BEGIN AFTER 'xx/xx' it could
> e.g. redirect the transaction to a node that's caught up far enough,
> instead of blocking. But that can't work even close to as easily if 
> it's
> something that has to be executed before transaction begin.
> 

I think that's a good point.

Also, I'm not sure how we'd expect a wait-for-LSN procedure to work 
inside a single-snapshot transaction. Would it throw an error inside a 
RR transaction block? Would it give a warning?

-- 
Anna Akenteva
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company





view thread (216+ messages)  latest in thread

Message-ID: <b797f7c14fd5e1227bb05fd964831465@postgrespro.ru>
Permalink:  ../b797f7c14fd5e1227bb05fd964831465@postgrespro.ru/
Also on:    postgresql.org/message-id/b797f7c14fd5e1227bb05fd964831465@postgrespro.ru

 · 

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: a.akenteva@postgrespro.ru, andres@anarazel.de, tgl@sss.pgh.pa.us, masao.fujii@oss.nttdata.com, a.kondratov@postgrespro.ru, horikyota.ntt@gmail.com, a.korotkov@postgrespro.ru, i.kartyshov@postgrespro.ru, amit.kapila16@gmail.com, pgsql-hackers@lists.postgresql.org
  Subject: Re: [HACKERS] make async slave to wait for lsn to be replayed
  In-Reply-To: <b797f7c14fd5e1227bb05fd964831465@postgrespro.ru>

* 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