add gc and its enablement flag to kube-controller-manager

cmd/kube-controller-manager/app/controllermanager.go

@@ -51,6 +51,7 @@ import (
 	endpointcontroller "k8s.io/kubernetes/pkg/controller/endpoint"
 	"k8s.io/kubernetes/pkg/controller/framework"
 	"k8s.io/kubernetes/pkg/controller/framework/informers"
+	"k8s.io/kubernetes/pkg/controller/garbagecollector"
 	"k8s.io/kubernetes/pkg/controller/gc"
 	"k8s.io/kubernetes/pkg/controller/job"
 	namespacecontroller "k8s.io/kubernetes/pkg/controller/namespace"
@@ -454,6 +455,23 @@ func StartControllers(s *options.CMServer, kubeClient *client.Client, kubeconfig
 	).Run()
 	time.Sleep(wait.Jitter(s.ControllerStartInterval.Duration, ControllerStartJitter))
 
+	if s.EnableGarbageCollector {
+		gcClientset := clientset.NewForConfigOrDie(restclient.AddUserAgent(kubeconfig, "generic-garbage-collector"))
+		groupVersionResources, err := gcClientset.Discovery().ServerPreferredResources()
+		if err != nil {
+			glog.Fatalf("Failed to get supported resources from server: %v", err)
+		}
+		clientPool := dynamic.NewClientPool(restclient.AddUserAgent(kubeconfig, "generic-garbage-collector"), dynamic.LegacyAPIPathResolverFunc)
+		garbageCollector, err := garbagecollector.NewGarbageCollector(clientPool, groupVersionResources)
+		if err != nil {
+			glog.Errorf("Failed to start the generic garbage collector")
+		} else {
+			// TODO: make this a flag of kube-controller-manager
+			workers := 5
+			go garbageCollector.Run(workers, wait.NeverStop)
+		}
+	}
+
 	// run the shared informers
 	for _, informer := range informers {
 		go informer.Run(wait.NeverStop)

cmd/kube-controller-manager/app/options/options.go

@@ -89,6 +89,7 @@ func NewCMServer() *CMServer {
 			KubeAPIBurst:            30,
 			LeaderElection:          leaderelection.DefaultLeaderElectionConfiguration(),
 			ControllerStartInterval: unversioned.Duration{Duration: 0 * time.Second},
+			EnableGarbageCollector:  false,
 		},
 	}
 	return &s
@@ -157,5 +158,6 @@ func (s *CMServer) AddFlags(fs *pflag.FlagSet) {
 	fs.Float32Var(&s.KubeAPIQPS, "kube-api-qps", s.KubeAPIQPS, "QPS to use while talking with kubernetes apiserver")
 	fs.Int32Var(&s.KubeAPIBurst, "kube-api-burst", s.KubeAPIBurst, "Burst to use while talking with kubernetes apiserver")
 	fs.DurationVar(&s.ControllerStartInterval.Duration, "controller-start-interval", s.ControllerStartInterval.Duration, "Interval between starting controller managers.")
+	fs.BoolVar(&s.EnableGarbageCollector, "enable-garbage-collector", s.EnableGarbageCollector, "Enables the generic garbage collector. MUST be synced with the corresponding flag of the kube-apiserver. WARNING: the generic garbage collector is an alpha feature.")
 	leaderelection.BindFlags(&s.LeaderElection, fs)
 }

docs/admin/kube-controller-manager.md

@@ -73,6 +73,7 @@ kube-controller-manager
       --deleting-pods-burst=10: Number of nodes on which pods are bursty deleted in case of node failure. For more details look into RateLimiter.
       --deleting-pods-qps=0.1: Number of nodes per second on which pods are deleted in case of node failure.
       --deployment-controller-sync-period=30s: Period for syncing the deployments.
+      --enable-garbage-collector[=false]: Enables the generic garbage collector. MUST be synced with the corresponding flag of the kube-apiserver. WARNING: the generic garbage collector is an alpha feature.
       --enable-hostpath-provisioner[=false]: Enable HostPath PV provisioning when running without a cloud provider. This allows testing and development of provisioning features.  HostPath provisioning is not supported in any way, won't work in a multi-node cluster, and should not be used for anything other than testing or development.
       --flex-volume-plugin-dir="/usr/libexec/kubernetes/kubelet-plugins/volume/exec/": Full path of the directory in which the flex volume plugin should search for additional third party volume plugins.
       --google-json-key="": The Google Cloud Platform Service Account JSON Key to use for authentication.
@@ -114,7 +115,7 @@ kube-controller-manager
       --terminated-pod-gc-threshold=12500: Number of terminated pods that can exist before the terminated pod garbage collector starts deleting terminated pods. If <= 0, the terminated pod garbage collector is disabled.
 ```
 
-###### Auto generated by spf13/cobra on 21-May-2016
+###### Auto generated by spf13/cobra on 26-May-2016
 
 
 <!-- BEGIN MUNGE: GENERATED_ANALYTICS -->

hack/verify-flags/known-flags.txt

@@ -110,6 +110,7 @@ e2e-output-dir
 e2e-verify-service-account
 enable-custom-metrics
 enable-debugging-handlers
+enable-garbage-collector
 enable-hostpath-provisioner
 enable-server
 enable-swagger-ui

pkg/apis/componentconfig/deep_copy_generated.go

@@ -134,6 +134,7 @@ func DeepCopy_componentconfig_KubeControllerManagerConfiguration(in KubeControll
 	if err := unversioned.DeepCopy_unversioned_Duration(in.ControllerStartInterval, &out.ControllerStartInterval, c); err != nil {
 		return err
 	}
+	out.EnableGarbageCollector = in.EnableGarbageCollector
 	return nil
 }
 

pkg/apis/componentconfig/types.go

@@ -556,6 +556,10 @@ type KubeControllerManagerConfiguration struct {
 	VolumeConfiguration VolumeConfiguration `json:"volumeConfiguration"`
 	// How long to wait between starting controller managers
 	ControllerStartInterval unversioned.Duration `json:"controllerStartInterval"`
+	// enables the generic garbage collector. MUST be synced with the
+	// corresponding flag of the kube-apiserver. WARNING: the generic garbage
+	// collector is an alpha feature.
+	EnableGarbageCollector bool `json:"enableGarbageCollector"`
 }
 
 // VolumeConfiguration contains *all* enumerated flags meant to configure all volume