k8s.io/kubernetes@v1.31.0-alpha.0.0.20240520171757-56147500dadc/cmd/kube-controller-manager/app/autoscaling.go (about)

     1  /*
     2  Copyright 2016 The Kubernetes Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  // Package app implements a server that runs a set of active
    18  // components.  This includes replication controllers, service endpoints and
    19  // nodes.
    20  package app
    21  
    22  import (
    23  	"context"
    24  
    25  	"k8s.io/client-go/dynamic"
    26  	"k8s.io/client-go/scale"
    27  	"k8s.io/controller-manager/controller"
    28  	"k8s.io/kubernetes/cmd/kube-controller-manager/names"
    29  	"k8s.io/kubernetes/pkg/controller/podautoscaler"
    30  	"k8s.io/kubernetes/pkg/controller/podautoscaler/metrics"
    31  
    32  	resourceclient "k8s.io/metrics/pkg/client/clientset/versioned/typed/metrics/v1beta1"
    33  	"k8s.io/metrics/pkg/client/custom_metrics"
    34  	"k8s.io/metrics/pkg/client/external_metrics"
    35  )
    36  
    37  func newHorizontalPodAutoscalerControllerDescriptor() *ControllerDescriptor {
    38  	return &ControllerDescriptor{
    39  		name:     names.HorizontalPodAutoscalerController,
    40  		aliases:  []string{"horizontalpodautoscaling"},
    41  		initFunc: startHorizontalPodAutoscalerControllerWithRESTClient,
    42  	}
    43  }
    44  
    45  func startHorizontalPodAutoscalerControllerWithRESTClient(ctx context.Context, controllerContext ControllerContext, controllerName string) (controller.Interface, bool, error) {
    46  
    47  	clientConfig := controllerContext.ClientBuilder.ConfigOrDie("horizontal-pod-autoscaler")
    48  	hpaClient := controllerContext.ClientBuilder.ClientOrDie("horizontal-pod-autoscaler")
    49  
    50  	apiVersionsGetter := custom_metrics.NewAvailableAPIsGetter(hpaClient.Discovery())
    51  	// invalidate the discovery information roughly once per resync interval our API
    52  	// information is *at most* two resync intervals old.
    53  	go custom_metrics.PeriodicallyInvalidate(
    54  		apiVersionsGetter,
    55  		controllerContext.ComponentConfig.HPAController.HorizontalPodAutoscalerSyncPeriod.Duration,
    56  		ctx.Done())
    57  
    58  	metricsClient := metrics.NewRESTMetricsClient(
    59  		resourceclient.NewForConfigOrDie(clientConfig),
    60  		custom_metrics.NewForConfig(clientConfig, controllerContext.RESTMapper, apiVersionsGetter),
    61  		external_metrics.NewForConfigOrDie(clientConfig),
    62  	)
    63  	return startHPAControllerWithMetricsClient(ctx, controllerContext, metricsClient)
    64  }
    65  
    66  func startHPAControllerWithMetricsClient(ctx context.Context, controllerContext ControllerContext, metricsClient metrics.MetricsClient) (controller.Interface, bool, error) {
    67  
    68  	hpaClient := controllerContext.ClientBuilder.ClientOrDie("horizontal-pod-autoscaler")
    69  	hpaClientConfig := controllerContext.ClientBuilder.ConfigOrDie("horizontal-pod-autoscaler")
    70  
    71  	// we don't use cached discovery because DiscoveryScaleKindResolver does its own caching,
    72  	// so we want to re-fetch every time when we actually ask for it
    73  	scaleKindResolver := scale.NewDiscoveryScaleKindResolver(hpaClient.Discovery())
    74  	scaleClient, err := scale.NewForConfig(hpaClientConfig, controllerContext.RESTMapper, dynamic.LegacyAPIPathResolverFunc, scaleKindResolver)
    75  	if err != nil {
    76  		return nil, false, err
    77  	}
    78  
    79  	go podautoscaler.NewHorizontalController(
    80  		ctx,
    81  		hpaClient.CoreV1(),
    82  		scaleClient,
    83  		hpaClient.AutoscalingV2(),
    84  		controllerContext.RESTMapper,
    85  		metricsClient,
    86  		controllerContext.InformerFactory.Autoscaling().V2().HorizontalPodAutoscalers(),
    87  		controllerContext.InformerFactory.Core().V1().Pods(),
    88  		controllerContext.ComponentConfig.HPAController.HorizontalPodAutoscalerSyncPeriod.Duration,
    89  		controllerContext.ComponentConfig.HPAController.HorizontalPodAutoscalerDownscaleStabilizationWindow.Duration,
    90  		controllerContext.ComponentConfig.HPAController.HorizontalPodAutoscalerTolerance,
    91  		controllerContext.ComponentConfig.HPAController.HorizontalPodAutoscalerCPUInitializationPeriod.Duration,
    92  		controllerContext.ComponentConfig.HPAController.HorizontalPodAutoscalerInitialReadinessDelay.Duration,
    93  	).Run(ctx, int(controllerContext.ComponentConfig.HPAController.ConcurrentHorizontalPodAutoscalerSyncs))
    94  	return nil, true, nil
    95  }