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+..
+ This work is licensed under a Creative Commons Attribution 3.0 Unported
+ License.
+
+ http://creativecommons.org/licenses/by/3.0/legalcode
+
+==================================
+SLA Performance degradation plugin
+==================================
+
+Problem description
+===================
+
+During density and reliability testing of OpenStack with Rally
+we observed test cases, during execution of which performance
+of OpenStack cluster has been drammatically degradated.
+
+Proposed change
+===============
+
+Develop a new Rally SLA plugin: *performance_degradation*
+
+This SLA plugin should find minimum and maximum duration of
+iterations completed without errors during Rally task execution.
+Assuming that minimum duration is 100%, it should calculate
+performance degradation against maximum duration.
+
+SLA plugin results:
+  - failure if performance degradation is more than value set
+  in plugin's max_degradation parameter;
+  - success if degradation is less
+  - performance degradation value as a percentage.
+
+How to enable this plugin:
+
+.. code:: json
+
+    "sla": {
+        "performance_degradation": {
+            "max_degradation": 50
+            }
+    }
+
+Alternatives
+------------
+
+None
+
+Implementation
+==============
+
+Assignee(s)
+-----------
+
+Primary assignee:
+
+anevenchannyy <anevenchannyy@mirantis.com>
+
+Work Items
+----------
+
+ - Implement plugin
+ - Add non-voting job with this plugin to the most important OpenStack services
+
+Dependencies
+============
+
+None