Re: Trigger file behavior with the standby - Mailing list pgsql-hackers

From Michael Paquier
Subject Re: Trigger file behavior with the standby
Date
Msg-id 20180320042818.GA13368@paquier.xyz
Whole thread Raw
In response to Trigger file behavior with the standby  (Keiko Oda <keiko713@gmail.com>)
Responses Re: Trigger file behavior with the standby
List pgsql-hackers
On Mon, Mar 19, 2018 at 01:27:21PM -0700, Keiko Oda wrote:
> I'm seeing the following behavior with a trigger file which is very
> confusing to me, I'd like to get some advice of what is the expected
> behavior of the trigger file with the standby.

This portion from the docs includes your answer:
https://www.postgresql.org/docs/devel/static/warm-standby.html#STANDBY-SERVER-OPERATION
"Standby mode is exited and the server switches to normal operation when
pg_ctl promote is run or a trigger file is found (trigger_file). Before
failover, any WAL immediately available in the archive or in pg_wal will
be restored, but no attempt is made to connect to the master.

So when creating a trigger file or signaling for promotion, any WAL
files available are first fetched, and then promotion happens.  In your
case all the WAL segments from the archives are retrieved first.
--
Michael

Attachment

pgsql-hackers by date:

Previous
From: Tom Lane
Date:
Subject: Re: IndexJoin memory problem using spgist and boxes
Next
From: Amit Langote
Date:
Subject: Re: ON CONFLICT DO UPDATE for partitioned tables