Merge pull request #69983 from rh-tokeefe/OSSM-5622

OSSM-5622: add topic for upgrade changes from service mesh 2.4 to 2.5 (2.5 Release)

Author: kcarmichael08

modules/ossm-upgrade-24-25-changes.adoc

@@ -0,0 +1,28 @@
+// Module included in the following assemblies:
+// * service_mesh/v2x/upgrading-ossm.adoc
+
+:_mod-docs-content-type: CONCEPT
+[id="ossm-upgrade-24-25-changes_{context}"]
+= Upgrade changes from version 2.4 to version 2.5
+
+== Istio OpenShift Routing (IOR) default setting change
+
+The default setting for Istio OpenShift Routing (IOR) has changed. The setting is now disabled by default.
+
+You can use IOR by setting the `enabled` field to `true` in the `spec.gateways.openshiftRoute` specification of the `ServiceMeshControlPlane` resource.
+
+[source,yaml]
+----
+apiVersion: maistra.io/v2
+kind: ServiceMeshControlPlane
+spec:
+  gateways:
+    openshiftRoute:
+      enabled: true
+----
+
+== Istio proxy concurrency configuration enhancement
+
+For consistency across deployments, Istio now configures the `concurrency` parameter based on the CPU limit allocated to the proxy container. For example, a limit of 2500m would set the `concurrency` parameter to 3. If you set the `concurrency` parameter to a value, Istio uses that value to configure how many threads the proxy runs instead of using the CPU limit. 
+
+Previously, the default setting for the parameter was 2. 

service_mesh/v2x/upgrading-ossm.adoc

@@ -36,6 +36,8 @@ Although you can deploy multiple versions of the control plane in the same clust
 
 For more information about migrating your extensions, refer to xref:../../service_mesh/v2x/ossm-extensions.adoc#ossm-extensions-migration-overview_ossm-extensions[Migrating from ServiceMeshExtension to WasmPlugin resources].
 
+include::modules/ossm-upgrade-24-25-changes.adoc[leveloffset=+2]
+
 include::modules/ossm-upgrade-23-24-changes.adoc[leveloffset=+2]
 
 include::modules/ossm-upgrade-22-23-changes.adoc[leveloffset=+2]