Hi,
On 7/22/19 8:08 PM, Michael Paquier wrote:
+ <xref linkend="guc-synchronous-commit"/> to something other than
Looks fine to me. Just a tiny nit. For the second reference to
synchronous_commit, I would change the link to a <varname> markup.
Sure.
Best regards,
Jesper
>From f6c5e9128e0779f928d94bf9bcc8813bf03150f0 Mon Sep 17 00:00:00 2001
From: jesperpedersen <[email protected]>
Date: Tue, 9 Jul 2019 13:14:25 -0400
Subject: [PATCH] Highlight that pg_receivewal doesn't apply WAL, and as such
synchronous-commit needs to be remote_write or lower.
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Author: Robert Haas
Review-by: Michael Paquier, Ãlvaro Herrera, Laurenz Albe and Jesper Pedersen
---
doc/src/sgml/ref/pg_receivewal.sgml | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/doc/src/sgml/ref/pg_receivewal.sgml b/doc/src/sgml/ref/pg_receivewal.sgml
index 0506120c00..a7536bed92 100644
--- a/doc/src/sgml/ref/pg_receivewal.sgml
+++ b/doc/src/sgml/ref/pg_receivewal.sgml
@@ -52,7 +52,15 @@ PostgreSQL documentation
Unlike the WAL receiver of a PostgreSQL standby server, <application>pg_receivewal</application>
by default flushes WAL data only when a WAL file is closed.
The option <option>--synchronous</option> must be specified to flush WAL data
- in real time.
+ in real time. Since <application>pg_receivewal</application> does not apply WAL,
+ you should not allow it to become a synchronous standby when
+ <xref linkend="guc-synchronous-commit"/> equals <literal>remote_apply</literal>.
+ If it does, it will appear to be a standby which never catches up,
+ which may cause commits to block. To avoid this, you should either
+ configure an appropriate value for <xref linkend="guc-synchronous-standby-names"/>, or
+ specify an <varname>application_name</varname> for
+ <application>pg_receivewal</application> that does not match it, or change the value of
+ <varname>synchronous_commit</varname> to something other than <literal>remote_apply</literal>.
</para>
<para>
--
2.21.0
