Added eviction thresholds to release notes

Author: ahardin-rh

release_notes/ocp_3_9_release_notes.adoc

@@ -678,6 +678,26 @@ See
 xref:../install_config/build_defaults_overrides.adoc#install-config-build-defaults-overrides[Configuring
 Global Build Defaults and Overrides] for more information.
 
+[[ocp-39-eviction-thresholds]]
+==== Default Hard Eviction Thresholds
+{product-title} uses the following default configuration for `eviction-hard`.
+
+[source, yaml]
+----
+...
+kubeletArguments:
+  eviction-hard:
+  - memory.available<100Mi
+  - nodefs.available<10%
+  - nodefs.inodesFree<5%
+  - imagefs.available<15%
+...
+----
+
+See
+xref:../admin_guide/out_of_resource_handling.adoc#admin-guide-handling-out-of-resource-errors[Handling
+Out of Resource Errors] for more information.
+
 [[ocp-39-web-console]]
 === Web Console