Mention max_lifetime option in disconnect_all

Author: josevalim

lib/ecto/adapters/sql.ex

@@ -478,9 +478,8 @@ defmodule Ecto.Adapters.SQL do
   Forces all connections in the repo pool to disconnect within the given interval.
 
   Once this function is called, the pool will disconnect all of its connections
-  as they are checked in or as they are pinged. Checked in connections will be
-  randomly disconnected within the given time interval. Pinged connections are
-  immediately disconnected - as they are idle (according to `:idle_interval`).
+  as they are checked in or as they are pinged. Checked in and idle connections
+  will be randomly disconnected within the given time interval.
 
   If the connection has a backoff configured (which is the case by default),
   disconnecting means an attempt at a new connection will be done immediately
@@ -489,6 +488,9 @@ defmodule Ecto.Adapters.SQL do
   disconnecting all connections may cause the pool supervisor to restart
   depending on the max_restarts/max_seconds configuration of the pool,
   so you will want to set those carefully.
+
+  If you need connections to be restarted periodically, set the `:max_lifetime`
+  option in your repository configuration instead.
   """
 
   @doc @to_sql_doc