Set fallocate_reserve to match upstream default

The upstream default for fallocate_reserve has just changed to 1% with
the inclusion of a "%" option for fallocate_reserve.
This PR sets the openstack-ansible default to match this value.

Change-Id: Iaafcb881dc067fa94d37e9eae93eed16d18c2f20

defaults/main.yml

@@ -136,7 +136,7 @@ swift_allow_all_users: False
 swift_recreate_keys: False
 swift_sorting_method: shuffle
 # Set the fallocate_reserve value which will reserve space and fail on PUTs above this value in bytes (Default 10GB)
-swift_fallocate_reserve: 10737418240
+swift_fallocate_reserve: "1%"
 swift_account_fallocate_reserve: "{{ swift_fallocate_reserve }}"
 swift_container_fallocate_reserve: "{{ swift_fallocate_reserve }}"
 swift_object_fallocate_reserve: "{{ swift_fallocate_reserve }}"

releasenotes/notes/swift-fallocate-reserve-ff513025da68bfed.yaml

@@ -1,8 +1,11 @@
 ---
 features:
-  - Allow the fallocate_reserve option to be set (in
-    bytes) for Swift, to help prevent disks from filling
-    up and prevent a situation where Swift is unable to
-    remove objects due to a lack of disk space. The
-    fallocate_reserve value to is set to a default of
-    10GB.
+  - The ``fallocate_reserve` option can now be set (in bytes or as a percentage) for swift
+    by using the ``swift_fallocate_reserve`` variable in
+    ``/etc/openstack_deploy/user_variables.yml``. This value is the amount of space to
+    reserve on a disk to prevent a situation where swift is unable to remove objects due
+    to a lack of available disk space to work with. The default value is 1% of the total
+    disk size.
+upgrade:
+  - The ``swift_fallocate_reserve`` default value has changed from 10737418240
+    (10GB) to 1% in order to match the OpenStack swift default setting.