migration: adding required footnote and link targets

Author: Sam Kleinman

source/administration/monitoring.txt

@@ -106,7 +106,7 @@ a MongoDB instance, in most cases you will not run this command
 directly. Nevertheless, all administrators should be familiar with the
 data provided by :dbcommand:`serverStatus`.
 
-.. seealso:: :method:`db.stats()` and :doc:`serverStatus data
+.. seealso:: :method:`db.serverStatus()` and :doc:`serverStatus data
    </reference/server-status/>`.
 
 ``replSetGetStatus``

source/administration/ulimit.txt

@@ -26,7 +26,7 @@ other processes:
 
 - track each incoming connection with a file descriptor *and* a thread.
 
-- track each internal thread or *pthread* as a system process. 
+- track each internal thread or *pthread* as a system process.
 
 ``mongod``
 ~~~~~~~~~~
@@ -38,7 +38,7 @@ other processes:
   :program:`mongod` instance when :setting:`journal` is ``true``.
 
 - In replica sets, each :program:`mongod` maintains a connection to
-  all other members of the set. 
+  all other members of the set.
 
 :program:`mongod` uses background threads for a number of internal
 processes, including :ref:`TTL collections <ttl-collections>`,
@@ -136,7 +136,7 @@ procedure for changing system limits on running systems.
 ``/proc`` File System
 ~~~~~~~~~~~~~~~~~~~~~
 
-.. note:: 
+.. note::
 
    This section applies only to Linux operating systems.
 
@@ -199,6 +199,8 @@ The output of the first command may resemble the following:
    Max realtime priority     65                   65
    Max realtime timeout      unlimited            unlimited            us
 
+.. _oom-killer:
+
 Recommended Settings
 --------------------
 
@@ -210,9 +212,16 @@ the following thresholds and settings are particularly important for
 - ``-t`` (cpu time): ``unlimited``
 - ``-v`` (virtual memory): ``unlimited``
 - ``-n`` (open files): ``64000``
-- ``-m`` (memory size): ``unlimited``
+- ``-m`` (memory size): ``unlimited`` [#resident-memory-size]_
 - ``-u`` (processes/threads): ``32000``
 
 Always remember to restart your :program:`mongod` and
 :program:`mongos` instances after changing the ``ulimit`` settings to
 make sure that the settings change takes effect.
+
+.. [#resident-memory-size] If you limit the resident memory size on a
+   system running MongoDB you risk allowing the operating system to
+   terminate the :program:`mongod` process under normal situations. Do
+   not set this value. If the operating system (i.e. Linux) kills your
+   :program:`mongod`, with the OOM killer, check the output of
+   :dbcommand:`serverStatus` and ensure MongoDB is not leaking memory.