Update README

readme.md

@@ -121,8 +121,7 @@ The memcached cache engine can take the following options:
   
   # Memcached options
   'compress' => false,
-  'persistent' => true,
-  'persistent_id' => 'mc',
+  'persistent' => false,
   'login' => null,
   'password => null,
   'serialize' => 'php'
@@ -135,13 +134,8 @@ Compress the cached data. Unlike memcache, memcache**d** can increment/decrement
 
 ### persistent
 
-*Default: `true`* 
-Use a persistent connection to the memcached server
-
-### persistent_id
-
-*Default: `mc`* 
-If you're using more than one persistent connection, you should assign them a different `persistent_id` each.
+*Default: `false`* 
+Use a persistent connection to the memcached server. To enable, set `persistent` to an unique string, to identify the connection. All configurations using the same persistent value will share a single underlying connection.
 
 ### login and password