Update README.md

README.md

@@ -136,10 +136,10 @@ this timeout.  A value of 0 means that idle connections are never removed from t
 :watch:``maxLifetime``<br/>
 This property controls the maximum lifetime of a connection in the pool.  When a connection
 reaches this timeout it will be retired from the pool, subject to a maximum variation of +30
-seconds, and average variation of +15 seconds.  An in-use connection will never be retired,
-only when it is closed will it then be removed.  We strongly recommend setting this value,
-and using something reasonable like 30 minutes or 1 hour.  A value of 0 indicates no maximum
-lifetime (infinite lifetime), subject of course to the ``idleTimeout`` setting.
+seconds.  An in-use connection will never be retired, only when it is closed will it then be
+removed.  **We strongly recommend setting this value, and it should be at least 30 seconds less
+than any database-level connection timeout.**  A value of 0 indicates no maximum lifetime 
+(infinite lifetime), subject of course to the ``idleTimeout`` setting.
 *Default: 1800000 (30 minutes)*
 
 :abc:``connectionTestQuery``<br/>