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-rw-r--r--doc/src/sgml/config.sgml34
-rw-r--r--doc/src/sgml/high-availability.sgml5
-rw-r--r--doc/src/sgml/runtime.sgml10
3 files changed, 27 insertions, 22 deletions
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 7e208a4b812..07b847a8e96 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -697,8 +697,7 @@ include_dir 'conf.d'
<para>
The default value is three connections. The value must be less
- than <varname>max_connections</varname> minus
- <xref linkend="guc-max-wal-senders"/>.
+ than <varname>max_connections</varname>.
This parameter can only be set at server start.
</para>
</listitem>
@@ -3495,24 +3494,25 @@ restore_command = 'copy "C:\\server\\archivedir\\%f" "%p"' # Windows
</term>
<listitem>
<para>
- Specifies the maximum number of concurrent connections from
- standby servers or streaming base backup clients (i.e., the
- maximum number of simultaneously running WAL sender
- processes). The default is 10. The value 0 means replication is
- disabled. WAL sender processes count towards the total number
- of connections, so this parameter's value must be less than
- <xref linkend="guc-max-connections"/> minus
- <xref linkend="guc-superuser-reserved-connections"/>.
- Abrupt streaming client disconnection might leave an orphaned
- connection slot behind until
- a timeout is reached, so this parameter should be set slightly
- higher than the maximum number of expected clients so disconnected
- clients can immediately reconnect. This parameter can only
- be set at server start.
- Also, <varname>wal_level</varname> must be set to
+ Specifies the maximum number of concurrent connections from standby
+ servers or streaming base backup clients (i.e., the maximum number of
+ simultaneously running WAL sender processes). The default is
+ <literal>10</literal>. The value <literal>0</literal> means
+ replication is disabled. Abrupt streaming client disconnection might
+ leave an orphaned connection slot behind until a timeout is reached,
+ so this parameter should be set slightly higher than the maximum
+ number of expected clients so disconnected clients can immediately
+ reconnect. This parameter can only be set at server start. Also,
+ <varname>wal_level</varname> must be set to
<literal>replica</literal> or higher to allow connections from standby
servers.
</para>
+
+ <para>
+ When running a standby server, you must set this parameter to the
+ same or higher value than on the master server. Otherwise, queries
+ will not be allowed in the standby server.
+ </para>
</listitem>
</varlistentry>
diff --git a/doc/src/sgml/high-availability.sgml b/doc/src/sgml/high-availability.sgml
index bbab7395a21..2b4dcd03c87 100644
--- a/doc/src/sgml/high-availability.sgml
+++ b/doc/src/sgml/high-availability.sgml
@@ -2179,6 +2179,11 @@ LOG: database system is ready to accept read only connections
</listitem>
<listitem>
<para>
+ <varname>max_wal_senders</varname>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
<varname>max_worker_processes</varname>
</para>
</listitem>
diff --git a/doc/src/sgml/runtime.sgml b/doc/src/sgml/runtime.sgml
index 1f78f6c9569..7de26e98ad8 100644
--- a/doc/src/sgml/runtime.sgml
+++ b/doc/src/sgml/runtime.sgml
@@ -720,13 +720,13 @@ psql: could not connect to server: No such file or directory
<row>
<entry><varname>SEMMNI</varname></entry>
<entry>Maximum number of semaphore identifiers (i.e., sets)</entry>
- <entry>at least <literal>ceil((max_connections + autovacuum_max_workers + max_worker_processes + 5) / 16)</literal> plus room for other applications</entry>
+ <entry>at least <literal>ceil((max_connections + autovacuum_max_workers + wax_wal_senders + max_worker_processes + 5) / 16)</literal> plus room for other applications</entry>
</row>
<row>
<entry><varname>SEMMNS</varname></entry>
<entry>Maximum number of semaphores system-wide</entry>
- <entry><literal>ceil((max_connections + autovacuum_max_workers + max_worker_processes + 5) / 16) * 17</literal> plus room for other applications</entry>
+ <entry><literal>ceil((max_connections + autovacuum_max_workers + max_wal_senders + max_worker_processes + 5) / 16) * 17</literal> plus room for other applications</entry>
</row>
<row>
@@ -785,13 +785,13 @@ psql: could not connect to server: No such file or directory
other applications. The maximum number of semaphores in the system
is set by <varname>SEMMNS</varname>, which consequently must be at least
as high as <varname>max_connections</varname> plus
- <varname>autovacuum_max_workers</varname> plus <varname>max_worker_processes</varname>,
- plus one extra for each 16
+ <varname>autovacuum_max_workers</varname> plus <varname>max_wal_senders</varname>,
+ plus <varname>max_worker_processes</varname>, plus one extra for each 16
allowed connections plus workers (see the formula in <xref
linkend="sysvipc-parameters"/>). The parameter <varname>SEMMNI</varname>
determines the limit on the number of semaphore sets that can
exist on the system at one time. Hence this parameter must be at
- least <literal>ceil((max_connections + autovacuum_max_workers + max_worker_processes + 5) / 16)</literal>.
+ least <literal>ceil((max_connections + autovacuum_max_workers + max_wal_senders + max_worker_processes + 5) / 16)</literal>.
Lowering the number
of allowed connections is a temporary workaround for failures,
which are usually confusingly worded <quote>No space