increase discovery burst for kube-controller-manager

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

@@ -466,8 +466,8 @@ func CreateControllerContext(s *config.CompletedConfig, rootClientBuilder, clien
 	}
 
 	// Use a discovery client capable of being refreshed.
-	discoveryClient := rootClientBuilder.ClientOrDie("controller-discovery")
+	discoveryClient := rootClientBuilder.DiscoveryClientOrDie("controller-discovery")
-	cachedClient := cacheddiscovery.NewMemCacheClient(discoveryClient.Discovery())
+	cachedClient := cacheddiscovery.NewMemCacheClient(discoveryClient)
 	restMapper := restmapper.NewDeferredDiscoveryRESTMapper(cachedClient)
 	go wait.Until(func() {
 		restMapper.Reset()

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

@@ -441,7 +441,8 @@ func startPodGCController(ctx ControllerContext) (http.Handler, bool, error) {
 
 func startResourceQuotaController(ctx ControllerContext) (http.Handler, bool, error) {
 	resourceQuotaControllerClient := ctx.ClientBuilder.ClientOrDie("resourcequota-controller")
-	discoveryFunc := resourceQuotaControllerClient.Discovery().ServerPreferredNamespacedResources
+	resourceQuotaControllerDiscoveryClient := ctx.ClientBuilder.DiscoveryClientOrDie("resourcequota-controller")
+	discoveryFunc := resourceQuotaControllerDiscoveryClient.ServerPreferredNamespacedResources
 	listerFuncForResource := generic.ListerFuncForResourceFunc(ctx.InformerFactory.ForResource)
 	quotaConfiguration := quotainstall.NewQuotaConfigurationForControllers(listerFuncForResource)
 
@@ -535,6 +536,7 @@ func startGarbageCollectorController(ctx ControllerContext) (http.Handler, bool,
 	}
 
 	gcClientset := ctx.ClientBuilder.ClientOrDie("generic-garbage-collector")
+	discoveryClient := ctx.ClientBuilder.DiscoveryClientOrDie("generic-garbage-collector")
 
 	config := ctx.ClientBuilder.ConfigOrDie("generic-garbage-collector")
 	metadataClient, err := metadata.NewForConfig(config)
@@ -564,7 +566,7 @@ func startGarbageCollectorController(ctx ControllerContext) (http.Handler, bool,
 
 	// Periodically refresh the RESTMapper with new discovery information and sync
 	// the garbage collector.
-	go garbageCollector.Sync(gcClientset.Discovery(), 30*time.Second, ctx.Stop)
+	go garbageCollector.Sync(discoveryClient, 30*time.Second, ctx.Stop)
 
 	return garbagecollector.NewDebugHandler(garbageCollector), true, nil
 }

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

@@ -45,6 +45,17 @@ func (m TestClientBuilder) ClientOrDie(name string) clientset.Interface {
 	return m.clientset
 }
 
+func (m TestClientBuilder) DiscoveryClient(name string) (discovery.DiscoveryInterface, error) {
+	return m.clientset.Discovery(), nil
+}
+func (m TestClientBuilder) DiscoveryClientOrDie(name string) discovery.DiscoveryInterface {
+	ret, err := m.DiscoveryClient(name)
+	if err != nil {
+		panic(err)
+	}
+	return ret
+}
+
 // FakeDiscoveryWithError inherits DiscoveryInterface(via FakeDiscovery) with some methods accepting testing data.
 type FakeDiscoveryWithError struct {
 	fakediscovery.FakeDiscovery

staging/src/k8s.io/controller-manager/pkg/clientbuilder/client_builder.go

@@ -17,6 +17,7 @@ limitations under the License.
 package clientbuilder
 
 import (
+	"k8s.io/client-go/discovery"
 	clientset "k8s.io/client-go/kubernetes"
 	restclient "k8s.io/client-go/rest"
 	"k8s.io/klog/v2"
@@ -30,6 +31,8 @@ type ControllerClientBuilder interface {
 	ConfigOrDie(name string) *restclient.Config
 	Client(name string) (clientset.Interface, error)
 	ClientOrDie(name string) clientset.Interface
+	DiscoveryClient(name string) (discovery.DiscoveryInterface, error)
+	DiscoveryClientOrDie(name string) discovery.DiscoveryInterface
 }
 
 // SimpleControllerClientBuilder returns a fixed client with different user agents
@@ -72,3 +75,28 @@ func (b SimpleControllerClientBuilder) ClientOrDie(name string) clientset.Interf
 	}
 	return client
 }
+
+// DiscoveryClientOrDie returns a discovery.DiscoveryInterface built from the ClientBuilder
+// Discovery is special because it will artificially pump the burst quite high to handle the many discovery requests.
+func (b SimpleControllerClientBuilder) DiscoveryClient(name string) (discovery.DiscoveryInterface, error) {
+	clientConfig, err := b.Config(name)
+	if err != nil {
+		return nil, err
+	}
+	// Discovery makes a lot of requests infrequently.  This allows the burst to succeed and refill to happen
+	// in just a few seconds.
+	clientConfig.Burst = 200
+	clientConfig.QPS = 20
+	return clientset.NewForConfig(clientConfig)
+}
+
+// DiscoveryClientOrDie returns a discovery.DiscoveryInterface built from the ClientBuilder with no error.
+// Discovery is special because it will artificially pump the burst quite high to handle the many discovery requests.
+// If it gets an error getting the client, it will log the error and kill the process it's running in.
+func (b SimpleControllerClientBuilder) DiscoveryClientOrDie(name string) discovery.DiscoveryInterface {
+	client, err := b.DiscoveryClient(name)
+	if err != nil {
+		klog.Fatal(err)
+	}
+	return client
+}

staging/src/k8s.io/controller-manager/pkg/clientbuilder/client_builder_dynamic.go

@@ -31,6 +31,7 @@ import (
 	"k8s.io/apimachinery/pkg/util/clock"
 	"k8s.io/apimachinery/pkg/util/wait"
 	apiserverserviceaccount "k8s.io/apiserver/pkg/authentication/serviceaccount"
+	"k8s.io/client-go/discovery"
 	clientset "k8s.io/client-go/kubernetes"
 	v1core "k8s.io/client-go/kubernetes/typed/core/v1"
 	restclient "k8s.io/client-go/rest"
@@ -155,6 +156,26 @@ func (t *DynamicControllerClientBuilder) ClientOrDie(name string) clientset.Inte
 	return client
 }
 
+func (t *DynamicControllerClientBuilder) DiscoveryClient(name string) (discovery.DiscoveryInterface, error) {
+	clientConfig, err := t.Config(name)
+	if err != nil {
+		return nil, err
+	}
+	// Discovery makes a lot of requests infrequently.  This allows the burst to succeed and refill to happen
+	// in just a few seconds.
+	clientConfig.Burst = 200
+	clientConfig.QPS = 20
+	return clientset.NewForConfig(clientConfig)
+}
+
+func (t *DynamicControllerClientBuilder) DiscoveryClientOrDie(name string) discovery.DiscoveryInterface {
+	client, err := t.DiscoveryClient(name)
+	if err != nil {
+		klog.Fatal(err)
+	}
+	return client
+}
+
 type tokenSourceImpl struct {
 	namespace          string
 	serviceAccountName string