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 <jesper.peder...@redhat.com>
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, Álvaro 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

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