PendingReleaseNotes: mention target_size_ratio change

Signed-off-by: Josh Durgin <jdurgin@redhat.com>
(cherry picked from commit 9118065c4c3803f8a2c26c28c69ffc9f14ff260a)

diff --git a/PendingReleaseNotes b/PendingReleaseNotes
index 812a9b2a0b04bb428affadde86ec4036de5be06e..0376f3caf05d0ad35ff65b88a7ad3391c61de282 100644 (file)
--- a/PendingReleaseNotes
+++ b/PendingReleaseNotes
@@ -4,3 +4,12 @@
 * Bucket notifications now support Kafka endpoints. This requires librdkafka of
   version 0.9.2 and up. Note that Ubuntu 16.04.6 LTS (Xenial Xerus) has an older
   version of librdkafka, and would require an update to the library.
+
+* The pool parameter ``target_size_ratio``, used by the pg autoscaler,
+  has changed meaning. It is now normalized across pools, rather than
+  specifying an absolute ratio. For details, see :ref:`pg-autoscaler`.
+  If you have set target size ratios on any pools, you may want to set
+  these pools to autoscale ``warn`` mode to avoid data movement during
+  the upgrade::
+
+    ceph osd pool set <pool-name> pg_autoscale_mode warn