istio.io/istio@v0.0.0-20240520182934-d79c90f27776/releasenotes/notes/route-collapse.yaml (about)

     1  apiVersion: release-notes/v2
     2  kind: feature
     3  area: traffic-management
     4  issue:
     5  - 28659
     6  releaseNotes:
     7  - |
     8    **Optimized** generated routing configuration to merge virtual hosts with the same routing configuration. This improves performance for Virtual Services with multiple hostnames defined.
     9  
    10  upgradeNotes:
    11  - title: EnvoyFilter `match.routeConfiguration.vhost.name` semantics change
    12    content: |
    13      `EnvoyFilter` matches rely on internal implementation details to match generated XDS segments, which is subject to change at any time.
    14  
    15      In this release, the [virtual host name match](https://istio.io/latest/docs/reference/config/networking/envoy-filter/#EnvoyFilter-RouteConfigurationMatch-VirtualHostMatch) may have different results.
    16  
    17      Previously, each domain name had its own virtual host. As an optimization, multiple domains may use a single virtual host.
    18      This means that a Envoy Filter previously matching a specific virtual host may now apply to more domains than in previous releases.
    19  
    20      This optimization may be temporarily disabled by setting `PILOT_ENABLE_ROUTE_COLLAPSE_OPTIMIZATION=false` on the Istiod deployment.