Merge pull request #56459 from oeuftete/add-grains-cache-exp-doc

Add grains_cache_expiration to minion conf doc

doc/ref/configuration/minion.rst

@@ -831,12 +831,28 @@ Default: ``False``
 
 The minion can locally cache grain data instead of refreshing the data
 each time the grain is referenced. By default this feature is disabled,
-to enable set grains_cache to ``True``.
+to enable set ``grains_cache`` to ``True``.
 
 .. code-block:: yaml
 
     grains_cache: False
 
+.. conf_minion:: grains_cache_expiration
+
+``grains_cache_expiration``
+---------------------------
+
+Default: ``300``
+
+Grains cache expiration, in seconds. If the cache file is older than this number
+of seconds then the grains cache will be dumped and fully re-populated with
+fresh data. Defaults to 5 minutes. Will have no effect if
+:conf_minion:`grains_cache` is not enabled.
+
+.. code-block:: yaml
+
+    grains_cache_expiration: 300
+
 .. conf_minion:: grains_deep_merge
 
 ``grains_deep_merge``