Add details for storage and knative services

config/nav.yml

@@ -131,6 +131,7 @@ nav:
           # TODO: Add security section to docs?
           - Configure resource requests and limits: serving/services/configure-requests-limits-services.md
           - HTTPS redirection: serving/services/http-protocol.md
+          - Configuring storage: serving/services/storage.md
         - Traffic management: serving/traffic-management.md
         - Configuring gradual rollout of traffic to Revisions: serving/rolling-out-latest-revision.md
         - Tag resolution: serving/tag-resolution.md

docs/serving/services/storage.md

@@ -0,0 +1,43 @@
+# Configuring storage for Knative services
+
+Knative Serving integrates with K8s storage capabilities via supporting a subset of ephemeral storage volumes and via PersistentVolumeClaims(PVCs) volume types.
+In detail Knative Serving supports emptyDir by default, secret, configmap, projection and PVCs volume types.
+For more details on volume configuration check the related [feature flags](../configuration/feature-flags.md) when applicable.
+
+Here is an example of using PVCs:
+
+```yaml
+apiVersion: serving.knative.dev/v1
+kind: Service
+...
+spec:
+  template:
+    spec:
+      containers:
+          ...
+          volumeMounts:
+            - mountPath: /data
+              name: mydata
+              readOnly: false
+      volumes:
+        - name: mydata
+          persistentVolumeClaim:
+            claimName: knative-pv-claim
+            readOnly: false
+---
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: knative-pv-claim
+spec:
+  accessModes:
+    - ReadWriteOnce
+  resources:
+    requests:
+      storage: 1Gi
+```
+
+The example assumes that the user has enabled PVC support via the corresponding feature flag.
+
+!!! warning
+    Mounting large volumes may add considerable overhead to the application's start up time.