doc: recommended to use apisix-standalone mode for installation. (#2470)

Author: AlinsRan

docs/en/latest/getting-started.md

@@ -43,9 +43,9 @@ Before installing APISIX Ingress Controller, ensure you have:
 1. A working Kubernetes cluster (version 1.26+)
 2. [Helm](https://helm.sh/) (version 3.8+) installed
 
-### Install APISIX and APISIX Ingress Controller
+### Install APISIX and APISIX Ingress Controller (Standalone API-driven mode)
 
-Install the Gateway API CRDs, APISIX, and APISIX Ingress Controller using the following commands:
+Install the Gateway API CRDs, [APISIX Standalone API-driven mode](https://apisix.apache.org/docs/apisix/deployment-modes/#api-driven-experimental), and APISIX Ingress Controller using the following commands:
 
 ```bash
 helm repo add apisix https://charts.apiseven.com
@@ -55,7 +55,11 @@ helm repo update
 helm install apisix \
   --namespace ingress-apisix \
   --create-namespace \
+  --set apisix.deployment.role=traditional \
+  --set apisix.deployment.role_traditional.config_provider=yaml \
+  --set etcd.enabled=false \
   --set ingress-controller.enabled=true \
+  --set ingress-controller.config.provider.type=apisix-standalone \
   --set ingress-controller.apisix.adminService.namespace=ingress-apisix \
   --set ingress-controller.gatewayProxy.createDefault=true \
   apisix/apisix
@@ -66,7 +70,7 @@ helm install apisix \
 Install the httpbin example application to test the configuration:
 
 ```bash
-https://raw.githubusercontent.com/apache/apisix-ingress-controller/refs/heads/v2.0.0/examples/httpbin/deployment.yaml
+kubectl apply -f https://raw.githubusercontent.com/apache/apisix-ingress-controller/refs/heads/v2.0.0/examples/httpbin/deployment.yaml
 ```
 
 ### Configure a Route

docs/en/latest/upgrade-guide.md

@@ -66,6 +66,12 @@ etcdserver:
 
 In 2.0.0, all data plane configurations must originate from the Ingress Controller. Configurations via Admin API or any external methods are no longer supported and will be ignored or may cause errors.
 
+#### APISIX With Etcd (Admin API) synchronization performance
+
+In APISIX Ingress Controller 2.0.0, ADC performs scheduled resource synchronization by comparing resources against the admin API response.
+
+Because the Admin API fills in default values, the submitted content may differ from the returned result. This breaks the diff, triggering full updates to data plane resources, causing cache invalidation and significant performance impact.
+
 ### Ingress Configuration Changes
 
 #### Configuration Path Changes