numad daemon causes performance degradation. (#5271)

* Add note about numad degredating performance

* external review complete

Author: MongoCaleb

source/administration/production-notes.txt

@@ -353,6 +353,9 @@ MongoDB checks NUMA settings on start up when deployed on Linux (since version
 2.0) and Windows (since version 2.6) machines. If the
 NUMA configuration may degrade performance, MongoDB prints a warning.
 
+The ``numad`` daemon process can also reduce :binary:`~bin.mongod` performance. 
+You should ensure ``numad`` is not enabled on MongoDB servers.
+
 .. seealso::
 
    - `The MySQL "swap insanity" problem and the effects of NUMA