DOCSP-35017 Add vm.force_cgroup_v2_swappiness recommendation to Prod Notes (#5604)

* DOCSP-35017 Add vm.force_cgroup_v2_swappiness recommendation to Prod Notes

* ES suggestions

* note placement

Author: ajhuh-mdb

source/administration/production-notes.txt

@@ -789,6 +789,14 @@ MongoDB performs best where swapping can be avoided or kept to a
 minimum. As such you should set ``vm.swappiness`` to either ``1`` or
 ``0`` depending on your application needs and cluster configuration.
 
+.. note:: 
+   
+   Most system and user processes run within a cgroup, which, by default, sets 
+   the ``vm.swappiness`` to ``60``. If you are running 
+   :abbr:`RHEL (Red Hat Enterprise Linux)` / CentOS, set 
+   ``vm.force_cgroup_v2_swappiness`` to ``1`` to ensure that the specified 
+   ``vm.swappiness`` value overrides any cgroup defaults.
+
 .. [#swappiness-kernel-version]
 
    With Linux kernel versions previous to ``3.5``, or