Configurable cache sizes of cachers

cmd/kube-apiserver/app/server.go

@@ -282,6 +282,8 @@ func Run(s *options.APIServer) error {
 	}
 
 	if s.EnableWatchCache {
+		glog.V(2).Infof("Initalizing cache sizes based on %dMB limit", s.TargetRAMMB)
+		cachesize.InitializeWatchCacheSizes(s.TargetRAMMB)
 		cachesize.SetWatchCacheSizes(s.WatchCacheSizes)
 	}
 

federation/cmd/federation-apiserver/app/server.go

@@ -142,6 +142,7 @@ func Run(s *genericoptions.ServerRunOptions) error {
 
 	// TODO: Move this to generic api server (Need to move the command line flag).
 	if s.EnableWatchCache {
+		cachesize.InitializeWatchCacheSizes(s.TargetRAMMB)
 		cachesize.SetWatchCacheSizes(s.WatchCacheSizes)
 	}
 

hack/verify-flags/exceptions.txt

@@ -39,7 +39,7 @@ cluster/rackspace/util.sh:    local node_ip=$(nova show --minimal ${NODE_NAMES[$
 cluster/saltbase/salt/cluster-autoscaler/cluster-autoscaler.manifest:{% set params = pillar['autoscaler_mig_config'] + " " + cloud_config -%}
 cluster/saltbase/salt/kube-admission-controls/init.sls:{% if 'LimitRanger' in pillar.get('admission_control', '') %}
 cluster/saltbase/salt/kube-apiserver/kube-apiserver.manifest:{% set enable_garbage_collector = pillar['enable_garbage_collector'] -%}
-cluster/saltbase/salt/kube-apiserver/kube-apiserver.manifest:{% set params = address + " " + etcd_servers + " " + etcd_servers_overrides + " " + cloud_provider + " " + cloud_config + " " + runtime_config + " " + admission_control + " " + service_cluster_ip_range + " " + client_ca_file + basic_auth_file + " " + min_request_timeout + " " + enable_garbage_collector -%}
+cluster/saltbase/salt/kube-apiserver/kube-apiserver.manifest:{% set params = address + " " + etcd_servers + " " + etcd_servers_overrides + " " + cloud_provider + " " + cloud_config + " " + runtime_config + " " + admission_control + " " + target_ram_mb + " " + service_cluster_ip_range + " " + client_ca_file + basic_auth_file + " " + min_request_timeout + " " + enable_garbage_collector -%}
 cluster/saltbase/salt/kube-controller-manager/kube-controller-manager.manifest:{% set enable_garbage_collector = pillar['enable_garbage_collector'] -%}
 cluster/saltbase/salt/kube-controller-manager/kube-controller-manager.manifest:{% set params = "--master=127.0.0.1:8080" + " " + cluster_name + " " + cluster_cidr + " " + allocate_node_cidrs + " " + service_cluster_ip_range + " " + terminated_pod_gc + " " + enable_garbage_collector + " " + cloud_provider  + " " + cloud_config + " " + service_account_key + " " + log_level + " " + root_ca_file -%}
 cluster/saltbase/salt/kube-proxy/kube-proxy.manifest:  {% set api_servers_with_port = api_servers + ":6443" -%}

hack/verify-flags/known-flags.txt

@@ -471,6 +471,7 @@ system-container
 system-pods-startup-timeout
 system-reserved
 target-port
+target-ram-mb
 tcp-services
 terminated-pod-gc-threshold
 test-timeout

pkg/genericapiserver/options/server_run_options.go

@@ -98,6 +98,7 @@ type ServerRunOptions struct {
 	// these; you can change this if you want to change the defaults (e.g.,
 	// for testing). This is not actually exposed as a flag.
 	DefaultStorageVersions string
+	TargetRAMMB            int
 	TLSCertFile            string
 	TLSPrivateKeyFile      string
 	TokenAuthFile          string
@@ -304,6 +305,9 @@ func (s *ServerRunOptions) AddFlags(fs *pflag.FlagSet) {
 		"Per-resource etcd servers overrides, comma separated. The individual override "+
 		"format: group/resource#servers, where servers are http://ip:port, semicolon separated.")
 
+	fs.IntVar(&s.TargetRAMMB, "target-ram-mb", s.TargetRAMMB,
+		"Memory limit for apiserver in MB (used to configure sizes of caches, etc.)")
+
 	fs.StringVar(&s.ExternalHost, "external-hostname", s.ExternalHost,
 		"The hostname to use when generating externalized URLs for this master (e.g. Swagger API Docs).")
 

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
 }

pkg/registry/configmap/etcd/etcd.go

@@ -18,6 +18,7 @@ package etcd
 
 import (
 	"k8s.io/kubernetes/pkg/api"
+	"k8s.io/kubernetes/pkg/registry/cachesize"
 	"k8s.io/kubernetes/pkg/registry/configmap"
 	"k8s.io/kubernetes/pkg/registry/generic"
 	"k8s.io/kubernetes/pkg/registry/generic/registry"
@@ -36,7 +37,13 @@ func NewREST(opts generic.RESTOptions) *REST {
 
 	newListFunc := func() runtime.Object { return &api.ConfigMapList{} }
 	storageInterface := opts.Decorator(
-		opts.Storage, 100, &api.ConfigMap{}, prefix, configmap.Strategy, newListFunc, storage.NoTriggerPublisher)
+		opts.Storage,
+		cachesize.GetWatchCacheSizeByResource(cachesize.ConfigMaps),
+		&api.ConfigMap{},
+		prefix,
+		configmap.Strategy,
+		newListFunc,
+		storage.NoTriggerPublisher)
 
 	store := &registry.Store{
 		NewFunc: func() runtime.Object {

pkg/registry/podsecuritypolicy/etcd/etcd.go

@@ -19,6 +19,7 @@ package etcd
 import (
 	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/apis/extensions"
+	"k8s.io/kubernetes/pkg/registry/cachesize"
 	"k8s.io/kubernetes/pkg/registry/generic"
 	"k8s.io/kubernetes/pkg/registry/generic/registry"
 	"k8s.io/kubernetes/pkg/registry/podsecuritypolicy"
@@ -38,7 +39,7 @@ func NewREST(opts generic.RESTOptions) *REST {
 	newListFunc := func() runtime.Object { return &extensions.PodSecurityPolicyList{} }
 	storageInterface := opts.Decorator(
 		opts.Storage,
-		100,
+		cachesize.GetWatchCacheSizeByResource(cachesize.PodSecurityPolicies),
 		&extensions.PodSecurityPolicy{},
 		prefix,
 		podsecuritypolicy.Strategy,

pkg/registry/storageclass/etcd/etcd.go

@@ -19,6 +19,7 @@ package etcd
 import (
 	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/apis/extensions"
+	"k8s.io/kubernetes/pkg/registry/cachesize"
 	"k8s.io/kubernetes/pkg/registry/generic"
 	"k8s.io/kubernetes/pkg/registry/generic/registry"
 	"k8s.io/kubernetes/pkg/registry/storageclass"
@@ -37,7 +38,7 @@ func NewREST(opts generic.RESTOptions) *REST {
 	newListFunc := func() runtime.Object { return &extensions.StorageClassList{} }
 	storageInterface := opts.Decorator(
 		opts.Storage,
-		100,
+		cachesize.GetWatchCacheSizeByResource(cachesize.StorageClasses),
 		&extensions.StorageClass{},
 		prefix,
 		storageclass.Strategy,