doc:  add pg_prewarm example
Discussion:
Author: Dong Wook Lee
Backpatch-through: 11
@@ -121,6 +121,19 @@ autoprewarm_dump_now() RETURNS int8
</listitem>
</varlistentry>
</variablelist>
+ <para>
+ These parameters must be set in <filename>postgresql.conf</filename>.
+ Typical usage might be:
+ </para>
+
+<programlisting>
+# postgresql.conf
+shared_preload_libraries = 'pg_prewarm'
+
+pg_prewarm.autoprewarm = true
+pg_prewarm.autoprewarm_interval = 300s
+
+</programlisting>
</sect2>
