use cache size to signal undecorated storage

Author: yastij

pkg/registry/cachesize/cachesize.go

@@ -39,6 +39,7 @@ func NewHeuristicWatchCacheSizes(expectedRAMCapacityMB int) map[schema.GroupReso
 	watchCacheSizes[schema.GroupResource{Resource: "nodes"}] = maxInt(5*clusterSize, 1000)
 	watchCacheSizes[schema.GroupResource{Resource: "pods"}] = maxInt(50*clusterSize, 1000)
 	watchCacheSizes[schema.GroupResource{Resource: "services"}] = maxInt(5*clusterSize, 1000)
+	watchCacheSizes[schema.GroupResource{Resource: "events"}] = 0
 	watchCacheSizes[schema.GroupResource{Resource: "apiservices", Group: "apiregistration.k8s.io"}] = maxInt(5*clusterSize, 1000)
 	return watchCacheSizes
 }

pkg/registry/core/event/storage/storage.go

@@ -40,10 +40,6 @@ func NewREST(optsGetter generic.RESTOptionsGetter, ttl uint64) *REST {
 		panic(err) // TODO: Propagate error up
 	}
 
-	// We explicitly do NOT do any decoration here - switching on Cacher
-	// for events will lead to too high memory consumption.
-	opts.Decorator = generic.UndecoratedStorage // TODO use watchCacheSize=-1 to signal UndecoratedStorage
-
 	store := &genericregistry.Store{
 		NewFunc:       func() runtime.Object { return &api.Event{} },
 		NewListFunc:   func() runtime.Object { return &api.EventList{} },

staging/src/k8s.io/apiserver/pkg/registry/generic/registry/storage_factory.go

@@ -42,7 +42,7 @@ func StorageWithCacher(capacity int) generic.StorageDecorator {
 		triggerFunc storage.TriggerPublisherFunc) (storage.Interface, factory.DestroyFunc) {
 
 		s, d := generic.NewRawStorage(storageConfig)
-		if capacity == 0 {
+		if capacity <= 0 {
 			klog.V(5).Infof("Storage caching is disabled for %T", objectType)
 			return s, d
 		}

staging/src/k8s.io/apiserver/pkg/server/options/etcd.go

@@ -229,6 +229,7 @@ func (f *SimpleRestOptionsFactory) GetRESTOptions(resource schema.GroupResource)
 		if !ok {
 			cacheSize = f.Options.DefaultWatchCacheSize
 		}
+		// depending on cache size this might return an undecorated storage
 		ret.Decorator = genericregistry.StorageWithCacher(cacheSize)
 	}
 	return ret, nil
@@ -262,6 +263,7 @@ func (f *StorageFactoryRestOptionsFactory) GetRESTOptions(resource schema.GroupR
 		if !ok {
 			cacheSize = f.Options.DefaultWatchCacheSize
 		}
+		// depending on cache size this might return an undecorated storage
 		ret.Decorator = genericregistry.StorageWithCacher(cacheSize)
 	}
 
@@ -285,7 +287,6 @@ func ParseWatchCacheSizes(cacheSizes []string) (map[schema.GroupResource]int, er
 		if size < 0 {
 			return nil, fmt.Errorf("watch cache size cannot be negative: %s", c)
 		}
-
 		watchCacheSizes[schema.ParseGroupResource(tokens[0])] = size
 	}
 	return watchCacheSizes, nil