Re: pg_receivewal documentation

Michael Paquier <michael@paquier.xyz>

From: Michael Paquier <michael@paquier.xyz>
To: Jehan-Guillaume de Rorthais <jgdr@dalibo.com>
Cc: Jesper Pedersen <jesper.pedersen@redhat.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2019-07-25T07:58:17Z
Lists: pgsql-hackers
On Wed, Jul 24, 2019 at 03:03:04PM +0200, Jehan-Guillaume de Rorthais wrote:
> Unless I am missing something, another solution might be to use a dedicated
> role to pg_receive{xlog|wal} with synchronous_commit lower than
> remote_apply.

Aren't you confused by the same thing as I was upthread [1]?
[1]: https://www.postgresql.org/message-id/20190710080423.GG1031@paquier.xyz

remote_apply affects all sessions.  So even if you use a replication
role with synchronous_commit = on and have pg_receivewal use that with
remote_apply set in postgresql.conf, then remote_apply is effective
for all the other sessions so these will still be stuck at commit
waiting for pg_receivewal to apply WAL if it is a synchronous
standby.
--
Michael

Commits

  1. Doc: Clarify interactions of pg_receivexlog with remote_apply

  2. Doc: Clarify interactions of pg_receivewal with remote_apply