DOCS-850 minor review edits

Author: Bob Grabar

source/tutorial/manage-the-database-profiler.txt

@@ -78,6 +78,9 @@ The threshold for slow operations applies to the entire
 :program:`mongod` instance. When you change the threshold, you change it
 for all databases on the instance.
 
+.. warning:: Changing the slow-operation threshold for the database
+   profiler also affects the logging subsystem's slow operation threshold.
+
 By default the threshold is 100 milliseconds. Databases with a log level
 of ``1`` will log operations slower than 100 milliseconds.
 
@@ -249,8 +252,9 @@ Profiler Overhead
 -----------------
 
 When enabled, profiling has a minor effect on performance. The
-``system.profile`` collection, which is a :term:`capped collection`, is
-set to several thousand typical profile documents by default.
+``system.profile`` collection is a :term:`capped collection` with a
+default size of 1 megabyte. It is able to store several thousand typical
+profile documents by default.
 
 To change the size of the ``system.profile`` collection, you must: