DOCS-971: edits

Author: Sam Kleinman

source/reference/mongoperf.txt

@@ -12,12 +12,12 @@ Synopsis
 --------
 
 :program:`mongoperf` is a utility to check disk I/O performance
-independently of MongoDB. :
+independently of MongoDB.
 
-It times tests of random disk I/O and
-presents the results.  ou can use :program:`mongoperf` for any case
-apart from MongoDB. he :samp:`mmf:false` mode is completely generic.
-In that mode is it somewhat analogous to tools such as `bonnie++
+It times tests of random disk I/O and presents the results. You can
+use :program:`mongoperf` for any case apart from MongoDB. The
+:setting:`~mongoperf.mmf` ``true`` mode is completely generic. In
+that mode is it somewhat analogous to tools such as `bonnie++
 <http://sourceforge.net/projects/bonnie/>`_ (albeit mongoperf is
 simpler).