Merge pull request #45675 from Princesso/merged-main-dev-1.30

Merge main branch into dev-1.30

content/en/docs/concepts/architecture/nodes.md

@@ -607,6 +607,8 @@ Learn more about the following:
 * [API definition for Node](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#node-v1-core).
 * [Node](https://git.k8s.io/design-proposals-archive/architecture/architecture.md#the-kubernetes-node)
   section of the architecture design document.
+* [Cluster autoscaling](/docs/concepts/cluster-administration/cluster-autoscaling/) to
+  manage the number and size of nodes in your cluster.
 * [Taints and Tolerations](/docs/concepts/scheduling-eviction/taint-and-toleration/).
 * [Node Resource Managers](/docs/concepts/policy/node-resource-managers/).
 * [Resource Management for Windows nodes](/docs/concepts/configuration/windows-resource-management/).

content/en/docs/concepts/cluster-administration/_index.md

@@ -52,6 +52,7 @@ Before choosing a guide, here are some considerations:
 ## Managing a cluster
 
 * Learn how to [manage nodes](/docs/concepts/architecture/nodes/).
+  * Read about [cluster autoscaling](/docs/concepts/cluster-administration/cluster-autoscaling/).
 
 * Learn how to set up and manage the [resource quota](/docs/concepts/policy/resource-quotas/) for shared clusters.
 

content/en/docs/concepts/cluster-administration/addons.md

@@ -1,7 +1,7 @@
 ---
 title: Installing Addons
 content_type: concept
-weight: 120
+weight: 150
 ---
 
 <!-- overview -->
@@ -109,6 +109,10 @@ installation instructions. The list does not try to be exhaustive.
   [Events](/docs/reference/kubernetes-api/cluster-resources/event-v1/) or
   [Node conditions](/docs/concepts/architecture/nodes/#condition).
 
+## Instrumentation
+
+* [kube-state-metrics](/docs/concepts/cluster-administration/kube-state-metrics)
+
 ## Legacy Add-ons
 
 There are several other add-ons documented in the deprecated

content/en/docs/concepts/cluster-administration/cluster-autoscaling.md

@@ -0,0 +1,117 @@
+---
+title: Cluster Autoscaling
+linkTitle: Cluster Autoscaling
+description: >-
+  Automatically manage the nodes in your cluster to adapt to demand.
+content_type: concept
+weight: 120
+---
+
+<!-- overview -->
+
+Kubernetes requires {{< glossary_tooltip text="nodes" term_id="node" >}} in your cluster to
+run {{< glossary_tooltip text="pods" term_id="pod" >}}. This means providing capacity for
+the workload Pods and for Kubernetes itself.
+
+You can adjust the amount of resources available in your cluster automatically:
+_node autoscaling_. You can either change the number of nodes, or change the capacity
+that nodes provide. The first approach is referred to as _horizontal scaling_, while the
+second is referred to as _vertical scaling_.
+
+Kubernetes can even provide multidimensional automatic scaling for nodes.
+
+<!-- body -->
+
+## Manual node management
+
+You can manually manage node-level capacity, where you configure a fixed amount of nodes;
+you can use this approach even if the provisioning (the process to set up, manage, and
+decommission) for these nodes is automated.
+
+This page is about taking the next step, and automating management of the amount of
+node capacity (CPU, memory, and other node resources) available in your cluster.
+
+## Automatic horizontal scaling {#autoscaling-horizontal}
+
+### Cluster Autoscaler
+
+You can use the [Cluster Autoscaler](https://github.com/kubernetes/autoscaler/tree/master/cluster-autoscaler) to manage the scale of your nodes automatically.
+The cluster autoscaler can integrate with a cloud provider, or with Kubernetes'
+[cluster API](https://github.com/kubernetes/autoscaler/blob/c6b754c359a8563050933a590f9a5dece823c836/cluster-autoscaler/cloudprovider/clusterapi/README.md),
+to achieve the actual node management that's needed.
+
+The cluster autoscaler adds nodes when there are unschedulable Pods, and
+removes nodes when those nodes are empty.
+
+#### Cloud provider integrations {#cluster-autoscaler-providers}
+
+The [README](https://github.com/kubernetes/autoscaler/tree/c6b754c359a8563050933a590f9a5dece823c836/cluster-autoscaler#readme)
+for the cluster autoscaler lists some of the cloud provider integrations
+that are available.
+
+## Cost-aware multidimensional scaling {#autoscaling-multi-dimension}
+
+### Karpenter {#autoscaler-karpenter}
+
+[Karpenter](https://karpenter.sh/) supports direct node management, via
+plugins that integrate with specific cloud providers, and can manage nodes
+for you whilst optimizing for overall cost.
+
+> Karpenter automatically launches just the right compute resources to
+> handle your cluster's applications. It is designed to let you take
+> full advantage of the cloud with fast and simple compute provisioning
+> for Kubernetes clusters.
+
+The Karpenter tool is designed to integrate with a cloud provider that
+provides API-driven server management, and where the price information for
+available servers is also available via a web API.
+
+For example, if you start some more Pods in your cluster, the Karpenter
+tool might buy a new node that is larger than one of the nodes you are
+already using, and then shut down an existing node once the new node
+is in service.
+
+#### Cloud provider integrations {#karpenter-providers}
+
+{{% thirdparty-content vendor="true" %}}
+
+There are integrations available between Karpenter's core and the following
+cloud providers:
+
+- [Amazon Web Services](https://github.com/aws/karpenter-provider-aws)
+- [Azure](https://github.com/Azure/karpenter-provider-azure)
+
+
+## Related components
+
+### Descheduler
+
+The [descheduler](https://github.com/kubernetes-sigs/descheduler) can help you
+consolidate Pods onto a smaller number of nodes, to help with automatic scale down
+when the cluster has space capacity.
+
+### Sizing a workload based on cluster size
+
+#### Cluster proportional autoscaler
+
+For workloads that need to be scaled based on the size of the cluster (for example
+`cluster-dns` or other system components), you can use the
+[_Cluster Proportional Autoscaler_](https://github.com/kubernetes-sigs/cluster-proportional-autoscaler).<br />
+
+The Cluster Proportional Autoscaler watches the number of schedulable nodes
+and cores, and scales the number of replicas of the target workload accordingly.
+
+#### Cluster proportional vertical autoscaler
+
+If the number of replicas should stay the same, you can scale your workloads vertically according to the cluster size using
+the [_Cluster Proportional Vertical Autoscaler_](https://github.com/kubernetes-sigs/cluster-proportional-vertical-autoscaler).
+This project is in **beta** and can be found on GitHub.
+
+While the Cluster Proportional Autoscaler scales the number of replicas of a workload, the Cluster Proportional Vertical Autoscaler
+adjusts the resource requests for a workload (for example a Deployment or DaemonSet) based on the number of nodes and/or cores
+in the cluster.
+
+
+## {{% heading "whatsnext" %}}
+
+- Read about [workload-level autoscaling](/docs/concepts/workloads/autoscaling/)