doc/radosgw: Improve config-ref.rst

Signed-off-by: Anthony D'Atri <[email protected]>

Author: anthonyeleven

doc/radosgw/config-ref.rst

@@ -264,18 +264,18 @@ QoS settings
 
 .. versionadded:: Nautilus
 
-The ``civetweb`` frontend has a threading model that uses a thread per
+The older and now non-default``civetweb`` frontend has a threading model that uses a thread per
 connection and hence is automatically throttled by :confval:`rgw_thread_pool_size`
-configurable when it comes to accepting connections. The newer ``beast`` frontend is
-not restricted by the thread pool size when it comes to accepting new
-connections, so a scheduler abstraction is introduced in the Nautilus release
-to support future methods of scheduling requests.
+when accepting connections. The newer and default ``beast`` frontend is
+not limited by the thread pool size when it comes to accepting new
+connections, so a scheduler abstraction was introduced in the Nautilus release
+to support additional methods of scheduling requests.
 
-Currently the scheduler defaults to a throttler which throttles the active
-connections to a configured limit. QoS based on mClock is currently in an
-*experimental* phase and not recommended for production yet. Current
-implementation of *dmclock_client* op queue divides RGW ops on admin, auth
-(swift auth, sts) metadata & data requests.
+Currently the scheduler defaults to a throttler that limits active
+connections to a configured limit. QoS rate limiting based on mClock is currently
+*experimental* phase and not recommended for production. The current
+implementation of the *dmclock_client* op queue divides RGW ops into admin, auth
+(swift auth, sts) metadata, and data requests.
 
 
 .. confval:: rgw_max_concurrent_requests
@@ -305,9 +305,9 @@ D4N Settings
 ============
 
 D4N is a caching architecture that utilizes Redis to speed up S3 object storage 
-operations by establishing shared databases between different RGW access points.
+operations by establishing shared databases among Ceph Object Gateway (RGW) daemons.
 
-Currently, the architecture can only function on one Redis instance at a time. 
+The D4N architecture can only function on one Redis instance at a time. 
 The address is configurable and can be changed by accessing the parameters 
 below.
 
@@ -324,18 +324,18 @@ below.
 Topic persistency settings
 ==========================
 
-Topic persistency will persistently push the notification until it succeeds.
+Topic persistency will repeatedly push notifications until they succeed.
 For more information, see `Bucket Notifications`_.
 
 The default behavior is to push indefinitely and as frequently as possible.
 With these settings you can control how long and how often to retry an
-unsuccessful notification. How long to persistently push can be controlled
-by providing maximum time of retention or maximum amount of retries.
-Frequency of persistent push retries can be controlled with the sleep duration
+unsuccessful notification by configuring the maximum retention time and/or or
+maximum number of retries.
+The interval between push retries can be configured via the sleep duration
 parameter.
 
-All of these values have default value 0 (persistent retention is indefinite,
-and retried as frequently as possible).
+All of these options default to the value `0`, which means that persistent
+retention is indefinite, and notifications are retried as frequently as possible.
 
 .. confval:: rgw_topic_persistency_time_to_live
 .. confval:: rgw_topic_persistency_max_retries