Re: [Patch] pg_rewind: options to use restore_command from recovery.conf or command line

From: Alexey Kondratov <a(dot)kondratov(at)postgrespro(dot)ru>
To: Alvaro Herrera <alvherre(at)2ndquadrant(dot)com>
Cc: Liudmila Mantrova <l(dot)mantrova(at)postgrespro(dot)ru>, Thomas Munro <thomas(dot)munro(at)gmail(dot)com>, Michael Paquier <michael(at)paquier(dot)xyz>, Andrey Borodin <x4mmm(at)yandex-team(dot)ru>, David Steele <david(at)pgmasters(dot)net>, Andres Freund <andres(at)anarazel(dot)de>, PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org>, Dmitry Dolgov <9erthalion6(at)gmail(dot)com>, vladimirlesk(at)yandex-team(dot)ru, dsarafan(at)yandex-team(dot)ru
Subject: Re: [Patch] pg_rewind: options to use restore_command from recovery.conf or command line
Date: 2019-09-26 12:08:22
Message-ID: 1088452e-19d6-c011-a48c-382e38360c71@postgrespro.ru
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On 01.08.2019 19:53, Alexey Kondratov wrote:
> On 26.07.2019 20:43, Liudmila Mantrova wrote:
>> On a more general note, I wonder if everyone is happy with the
>> --using-postgresql-conf option name, or we should continue searching
>> for a narrower term. Unfortunately, I don't have any better
>> suggestions right now, but I believe it should be clear that its
>> purpose is to fetch missing WAL files for target. What do you think?
>>
>
> I don't like it either, but this one was my best guess then. Maybe
> --restore-target-wal instead of --using-postgresql-conf will be
> better? And --target-restore-command instead of --restore-command if
> we want to specify that this is restore_command for target server?
>

As Alvaro correctly pointed in the nearby thread [1], we've got an
interference regarding -R command line argument. I agree that it's a
good idea to reserve -R for recovery configuration write to be
consistent with pg_basebackup, so I've updated my patch to use another
letters:

1. -c/--restore-target-wal --- to use restore_command from postgresql.conf
2. -C/--target-restore-command --- to pass restore_command as a command
line argument

Updated and rebased patch is attached. However, now I'm wondering, do we
actually need 1. as a separated option and not being enabled by default?
I cannot imagine a situation, when restore_command is set in the
postgresql.conf and someone prefer pg_rewind to fail instead of fetching
missed WALs automatically, but maybe there are some cases?

[1]
https://www.postgresql.org/message-id/20190925174812.GA4916%40alvherre.pgsql

--
Alexey Kondratov

Postgres Professional https://www.postgrespro.com
Russian Postgres Company

Attachment Content-Type Size
v10-0001-pg_rewind-options-to-use-restore_command-from-co.patch text/x-patch 22.9 KB

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Antonin Houska 2019-09-26 12:08:33 Re: Attempt to consolidate reading of XLOG page
Previous Message Christoph Berg 2019-09-26 11:04:26 Unstable select_parallel regression output in 12rc1