api:Add a flag to disable overprovisioning in ClusterLoadAssignment (#8080)

* api:Add a flag to disable overprovisioning in ClusterLoadAssignment

Signed-off-by: Jie Chen <jiechen@google.com>

* api:Add [#next-major-version and [#not-implemented-hide to the comment
for field of disable_overprovisioning in ClusterLoadAssignment
Signed-off-by: Jie Chen <jiechen@google.com>

* api:Refine comments for the new added bool flag as suggested.
Signed-off-by: Jie Chen <jiechen@google.com>

Mirrored from https://github.com/envoyproxy/envoy @ b28edcae3da369ed9969796f89118c1f898a27d9

envoy/api/v2/eds.proto

@@ -117,6 +117,17 @@ message ClusterLoadAssignment {
     // are considered stale and should be marked unhealthy.
     // Defaults to 0 which means endpoints never go stale.
     google.protobuf.Duration endpoint_stale_after = 4 [(validate.rules).duration.gt.seconds = 0];
+
+    // The flag to disable overprovisioning. If it is set to true,
+    // :ref:`overprovisioning factor
+    // <arch_overview_load_balancing_overprovisioning_factor>` will be ignored
+    // and Envoy will not perform graceful failover between priority levels or
+    // localities as endpoints become unhealthy. Otherwise Envoy will perform
+    // graceful failover as :ref:`overprovisioning factor
+    // <arch_overview_load_balancing_overprovisioning_factor>` suggests.
+    // [#next-major-version: Unify with overprovisioning config as a single message.]
+    // [#not-implemented-hide:]
+    bool disable_overprovisioning = 5;
   }
 
   // Load balancing policy settings.