diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index fea683cb49c..d49a717648b 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -2726,7 +2726,7 @@ include_dir 'conf.d'
          </itemizedlist>
         </para>
         <para>
-         This parameter can only be set at server start.
+         This parameter can only be set at server start. The default is <literal>worker</literal>.
         </para>
        </listitem>
       </varlistentry>