Configurable cache sizes of cachers

pkg/registry/cachesize/cachesize.go

@@ -31,6 +31,7 @@ const (
 	CertificateSigningRequests Resource = "certificatesigningrequests"
 	ClusterRoles               Resource = "clusterroles"
 	ClusterRoleBindings        Resource = "clusterrolebindings"
+	ConfigMaps                 Resource = "configmaps"
 	Controllers                Resource = "controllers"
 	Daemonsets                 Resource = "daemonsets"
 	Deployments                Resource = "deployments"
@@ -47,6 +48,7 @@ const (
 	PersistentVolumes          Resource = "persistentvolumes"
 	PersistentVolumeClaims     Resource = "persistentvolumeclaims"
 	Pods                       Resource = "pods"
+	PodSecurityPolicies        Resource = "podsecuritypolicies"
 	PodTemplates               Resource = "podtemplates"
 	Replicasets                Resource = "replicasets"
 	ResourceQuotas             Resource = "resourcequotas"
@@ -56,40 +58,36 @@ const (
 	Secrets                    Resource = "secrets"
 	ServiceAccounts            Resource = "serviceaccounts"
 	Services                   Resource = "services"
+	StorageClasses             Resource = "storageclasses"
+
+	// Default value of watch cache size for a resource if not specified.
+	defaultWatchCacheSize = 100
 )
 
+// TODO: This shouldn't be a global variable.
 var watchCacheSizes map[Resource]int
 
 func init() {
 	watchCacheSizes = make(map[Resource]int)
-	watchCacheSizes[CertificateSigningRequests] = 1000
-	watchCacheSizes[ClusterRoles] = 100
-	watchCacheSizes[ClusterRoleBindings] = 100
-	watchCacheSizes[Controllers] = 100
-	watchCacheSizes[Daemonsets] = 100
-	watchCacheSizes[Deployments] = 100
-	watchCacheSizes[Endpoints] = 1000
-	watchCacheSizes[HorizontalPodAutoscalers] = 100
-	watchCacheSizes[Ingress] = 100
-	watchCacheSizes[PetSet] = 100
-	watchCacheSizes[PodDisruptionBudget] = 100
-	watchCacheSizes[Jobs] = 100
-	watchCacheSizes[LimitRanges] = 100
-	watchCacheSizes[Namespaces] = 100
-	watchCacheSizes[NetworkPolicys] = 100
-	watchCacheSizes[Nodes] = 1000
-	watchCacheSizes[PersistentVolumes] = 100
-	watchCacheSizes[PersistentVolumeClaims] = 100
-	watchCacheSizes[Pods] = 1000
-	watchCacheSizes[PodTemplates] = 100
-	watchCacheSizes[Replicasets] = 100
-	watchCacheSizes[ResourceQuotas] = 100
-	watchCacheSizes[ScheduledJobs] = 100
-	watchCacheSizes[Roles] = 100
-	watchCacheSizes[RoleBindings] = 100
-	watchCacheSizes[Secrets] = 100
-	watchCacheSizes[ServiceAccounts] = 100
-	watchCacheSizes[Services] = 100
+}
+
+func InitializeWatchCacheSizes(expectedRAMCapacityMB int) {
+	// This is the heuristics that from memory capacity is trying to infer
+	// the maximum number of nodes in the cluster and set cache sizes based
+	// on that value.
+	// From our documentation, we officially recomment 120GB machines for
+	// 2000 nodes, and we scale from that point. Thus we assume ~60MB of
+	// capacity per node.
+	// TODO: Revisit this heuristics
+	clusterSize := expectedRAMCapacityMB / 60
+
+	// We should specify cache size for a given resource only if it
+	// is supposed to have non-default value.
+	//
+	// TODO: Figure out which resource we should have non-default value.
+	watchCacheSizes[Endpoints] = maxInt(10*clusterSize, 1000)
+	watchCacheSizes[Nodes] = maxInt(3*clusterSize, 1000)
+	watchCacheSizes[Pods] = maxInt(10*clusterSize, 1000)
 }
 
 func SetWatchCacheSizes(cacheSizes []string) {
@@ -111,5 +109,15 @@ func SetWatchCacheSizes(cacheSizes []string) {
 }
 
 func GetWatchCacheSizeByResource(resource Resource) int {
-	return watchCacheSizes[resource]
+	if value, found := watchCacheSizes[resource]; found {
+		return value
+	}
+	return defaultWatchCacheSize
+}
+
+func maxInt(a, b int) int {
+	if a > b {
+		return a
+	}
+	return b
 }