doc/rados: improve "scrubbing" explanation

Improve the English describing the operation of scrubbing PGs in
doc/rados/configuration/osd-config-ref.rst.

Co-authored-by: Ronen Friedman <rfriedma@redhat.com>
Signed-off-by: Zac Dover <zac.dover@proton.me>
(cherry picked from commit 19b139932d8aef9b47e1fa9c400c3f73b5cb3d7b)

diff --git a/doc/rados/configuration/osd-config-ref.rst b/doc/rados/configuration/osd-config-ref.rst
index fb210da42d3803125374deaa6849a9f3c4bab7a4..6867a92150459c157b0a01bf7c01cd9ecf370971 100644 (file)
--- a/doc/rados/configuration/osd-config-ref.rst
+++ b/doc/rados/configuration/osd-config-ref.rst
@@ -145,17 +145,20 @@ See `Pool & PG Config Reference`_ for details.
 Scrubbing
 =========
 
-In addition to making multiple copies of objects, Ceph ensures data integrity by
-scrubbing placement groups. Ceph scrubbing is analogous to ``fsck`` on the
-object storage layer. For each placement group, Ceph generates a catalog of all
-objects and compares each primary object and its replicas to ensure that no
-objects are missing or mismatched. Light scrubbing (daily) checks the object
-size and attributes.  Deep scrubbing (weekly) reads the data and uses checksums
-to ensure data integrity.
-
-Scrubbing is important for maintaining data integrity, but it can reduce
-performance. You can adjust the following settings to increase or decrease
-scrubbing operations.
+One way that Ceph ensures data integrity is by "scrubbing" placement groups.
+Ceph scrubbing is analogous to ``fsck`` on the object storage layer. Ceph
+generates a catalog of all objects in each placement group and compares each
+primary object to its replicas, ensuring that no objects are missing or
+mismatched. Light scrubbing checks the object size and attributes, and is
+usually done daily. Deep scrubbing reads the data and uses checksums to ensure
+data integrity, and is usually done weekly. The freqeuncies of both light
+scrubbing and deep scrubbing are determined by the cluster's configuration,
+which is fully under your control and subject to the settings explained below
+in this section.
+
+Although scrubbing is important for maintaining data integrity, it can reduce
+the performance of the Ceph cluster. You can adjust the following settings to
+increase or decrease the frequency and depth of scrubbing operations.
 
 
 .. confval:: osd_max_scrubs