Control plane scheduling component kube-scheduler - Container Service for Kubernetes

kube-scheduler is a control plane component that schedules pods to nodes that meet resource usage and pod scheduling requirements.

Introduction

kube-scheduler selects a valid node for each pod in the scheduling queue based on the resource request of the pod and the allocatable resources on the node. In addition, kube-scheduler can sort all valid nodes in a specific order and select a suitable node to host the pod. By default, kube-scheduler spreads pods across nodes based on pod requests.

Usage notes

kube-scheduler is automatically installed in a Kubernetes cluster. You can use kube-scheduler without additional configurations. To update kube-scheduler, log on to the Container Service for Kubernetes (ACK) console, click the cluster that you want to manage, and then choose Operations > Add-ons.

Release notes

Release notes for V1.28

Version number	Release date	Description
v1.28.3-aliyun-5.8-89c55520	2023-10-28	All features provided by earlier versions are supported in kube-scheduler V1.28.

Release notes for V1.26

Version number	Release date	Description
v1.26.3-aliyun-5.8-a1482f93	2023-10-16	Pods can be scheduled to Windows nodes. Coscheduling is optimized to accelerate the scheduling of multiple concurrent tasks and reduce blocked tasks.
v1.26.3-aliyun-5.7-2f57d3ff	2023-09-20	The following issue is fixed: When GPU sharing is used to schedule pods, kube-scheduler occasionally fails to admit pods. A plug-in is added to kube-scheduler to detect the available IP addresses on a node. If no IP addresses are available on the node, pods are no longer scheduled to the node. A topology-aware scheduling plug-in is added to kube-scheduler. This plug-in can schedule pods to the same topological domain and automatically retries scheduling on multiple topological domains. kube-scheduler updates the usage and request information about ElasticQuotaTree every one second.
v1.26.3-aliyun-5.5-8b98a1cc	2023-07-05	The following issue is fixed: Pods occasionally remain in the Pending state for a long time when Coscheduling is used. User experience is optimized for using Coscheduling and elastic node pools at the same time. If some pods in a pod group cannot be scheduled or created due to incorrect node selector configurations, the other pods in the PodGroup will not trigger scale-out activities.
v1.26.3-aliyun-5.4-21b4da4c	2023-07-03	The issue that the max parameter in a ResourcePolicy does not take effect is fixed. The impact of a large number of pending pods on the kube-scheduler performance is mitigated. This update brings the throughput of kube-scheduler up to a level close to that when the cluster does not contain pending pods.
v1.26.3-aliyun-5.1-58a821bf	2023-05-26	Fields such as min-available and Matchpolicy can be updated for PodGroups.
v1.26.3-aliyun-5.0-7b1ccc9d	2023-05-22	The maximum number of replicated pods can be specified in the Unit field when you configure priority-based resource scheduling. Topology-aware GPU scheduling is supported.
v1.26.3-aliyun-4.1-a520c096	2023-04-27	Nodes are not added by cluster-autoscaler when the elastic quota is exhausted or when pods are insufficient for gang scheduling.

Release notes for V1.24

Version number	Release date	Description
v1.24.6-aliyun-5.8-49fd8652	2023-10-16	Pods can be scheduled to Windows nodes. Coscheduling is optimized to accelerate the scheduling of multiple concurrent tasks and reduce blocked tasks.
v1.24.6-aliyun-5.7-62c7302c	2023-09-20	The following issue is fixed: When GPU sharing is used to schedule pods, kube-scheduler occasionally fails to admit pods.
v1.24.6-aliyun-5.6-2bb99440	2023-08-31	A plug-in is added to kube-scheduler to detect the available IP addresses on a node. If no IP addresses are available on the node, pods are no longer scheduled to the node. A topology-aware scheduling plug-in is added to kube-scheduler. This plug-in can schedule pods to the same topological domain and automatically retries scheduling on multiple topological domains. kube-scheduler updates the usage and request information about ElasticQuotaTree every one second.
v1.24.6-aliyun-5.5-5e8aac79	2023-07-05	The following issue is fixed: Pods occasionally remain in the Pending state for a long time when Coscheduling is used. User experience is optimized for using Coscheduling and elastic node pools at the same time. If some pods in a pod group cannot be scheduled or created due to incorrect node selector configurations, the other pods in the PodGroup will not trigger scale-out activities.
v1.24.6-aliyun-5.4-d81e785e	2023-07-03	The issue that the max parameter in a ResourcePolicy does not take effect is fixed. The impact of a large number of pending pods on the kube-scheduler performance is mitigated. This update brings the throughput of kube-scheduler up to a level close to that when the cluster does not contain pending pods.
v1.24.6-aliyun-5.1-95d8a601	2023-05-26	Fields such as min-available and Matchpolicy can be updated for Coscheduling.
v1.24.6-aliyun-5.0-66224258	2023-05-22	The maximum number of replicated pods can be specified in the Unit field when you configure priority-based resource scheduling. Topology-aware GPU scheduling is supported.
v1.24.6-aliyun-4.1-18d8d243	2023-03-31	Elastic resources can be used to schedule pods to ARM-based virtual nodes.
v1.24.6-4.0-330eb8b4-aliyun	2023-03-01	GPU sharing: The kube-scheduler status error during GPU-accelerated node downgrades is fixed. The issue that you cannot allocate all GPU memory of a GPU-accelerated node is fixed. Pods on GPU-accelerated nodes can be preempted. Coscheduling: Gangs can be claimed by using PodGroups or calling the Koordinator API. Gang scheduling retries can be controlled by claiming a matchpolicy. Gang groups are supported. The naming of gangs must meet the rules for DNS subdomains. Custom parameters are added to support Loadaware-related configurations.
v1.24.6-3.2-4f45222b-aliyun	2023-01-13	The issue that the GPU memory used by pods cannot be displayed as normal due to the incorrect shared GPU memory information is fixed.
v1.24.6-ack-3.1	2022-11-14	The score feature is enabled for GPU sharing by default. The score feature is disabled by default in earlier versions. Load-aware scheduling is supported.
v1.24.6-ack-3.0	2022-09-27	Capacity scheduling is supported.
v1.24.3-ack-2.0	2022-09-21	GPU sharing is supported. Coscheduling is supported. Elastic Container Instance-based scheduling is supported. Intelligent CPU scheduling is supported.

Release notes for V1.22

Version number	Release date	Description
v1.22.15-aliyun-5.8-29a640ae	2023-10-16	Pods can be scheduled to Windows nodes. Coscheduling is optimized to accelerate the scheduling of multiple concurrent tasks and reduce blocked tasks.
v1.22.15-aliyun-5.7-bfcffe21	2023-09-20	The following issue is fixed: When GPU sharing is used to schedule pods, kube-scheduler occasionally fails to admit pods.
v1.22.15-aliyun-5.6-6682b487	2023-08-14	A plug-in is added to kube-scheduler to detect the available IP addresses on a node. If no IP addresses are available on the node, pods are no longer scheduled to the node. A topology-aware scheduling plug-in is added to kube-scheduler. This plug-in can schedule pods to the same topological domain and automatically retries scheduling on multiple topological domains. kube-scheduler updates the usage and request information about ElasticQuotaTree every one second.
v1.22.15-aliyun-5.5-82f32f68	2023-07-05	The following issue is fixed: Pods occasionally remain in the Pending state for a long time when Coscheduling is used. The user experience of PodGroups in elastic node pools is optimized. If some pods in a pod group cannot be scheduled or created due to incorrect node selector configurations, the other pods in the PodGroup will not trigger scale-out activities.
v1.22.15-aliyun-5.4-3b914a05	2023-07-03	The issue that the max parameter in a ResourcePolicy does not take effect is fixed. The impact of a large number of pending pods on the kube-scheduler performance is mitigated. This update brings the throughput of kube-scheduler up to a level close to that when the cluster does not contain pending pods.
v1.22.15-aliyun-5.1-8a479926	2023-05-26	Fields such as min-available and Matchpolicy can be updated for PodGroups.
v1.22.15-aliyun-5.0-d1ab67d9	2023-05-22	The maximum number of replicated pods can be specified in the Unit field when you configure priority-based resource scheduling. Topology-aware GPU scheduling is supported.
v1.22.15-aliyun-4.1-aec17f35	2023-03-31	Elastic resources can be used to schedule pods to ARM-based virtual nodes.
v1.22.15-aliyun-4.0-384ca5d5	2023-03-03	GPU sharing: The kube-scheduler status error during GPU-accelerated node downgrades is fixed. The issue that you cannot allocate all GPU memory of a GPU-accelerated node is fixed. Pods on GPU-accelerated nodes can be preempted. Coscheduling: Gangs can be claimed by using PodGroups or calling the Koordinator API. Gang scheduling retries can be controlled by claiming a matchpolicy. Gang groups are supported. The naming of gangs must meet the rules for DNS subdomains. Custom parameters are added to support Loadaware-related configurations.
v1.22.15-2.1-a0512525-aliyun	2023-01-10	The issue that the GPU memory used by pods cannot be displayed as normal due to the incorrect shared GPU memory information is fixed.
v1.22.15-ack-2.0	2022-11-30	Custom parameter settings are supported. Load-aware scheduling is supported. Priority-based scheduling is supported. You can use this feature to schedule pods to node pools based on priorities. The computing power of GPUs can be shared.
v1.22.3-ack-1.1	2022-02-27	The issue that GPU sharing and scheduling do not work when the cluster contains only one node is fixed.
v1.22.3-ack-1.0	2021-01-04	Intelligent CPU scheduling is supported. Coscheduling is supported. Capacity scheduling is supported. Elastic Container Instance-based scheduling is supported. GPU sharing is supported.

Release notes for V1.20

Version number	Release date	Description
v1.20.11-aliyun-10.3-416caa03	2023-05-26	The cache error that occasionally occurs during GPU sharing in earlier Kubernetes versions is fixed.
v1.20.11-aliyun-10.2-f4a371d3	2023-04-27	Elastic resources can be used to schedule pods to ARM-based virtual nodes. The issue that load-aware scheduling does not work as expected when the CPU usage of pods on a node exceeds the CPU request of the pods is fixed.
v1.20.11-aliyun-10.0-ae867721	2023-04-03	The Matchpolicy field is supported by Coscheduling.
v1.20.11-aliyun-9.2-a8f8c908	2023-03-08	CapacityScheduling: The kube-scheduler status error caused by quotas with the same name is fixed. Cloud disk scheduling is supported. GPU sharing and scheduling: The kube-scheduler status error during GPU-accelerated node downgrades is fixed. The occasional issue that you cannot allocate all GPU memory of a GPU-accelerated node is fixed. Pods on GPU-accelerated nodes can be preempted. Topology-aware CPU scheduling: Pods that have CPU scheduling enabled are not scheduled to nodes that have Numa disabled. Custom parameters are added.
v1.20.4-ack-8.0	2022-08-29	Bugs are fixed.
v1.20.4-ack-7.0	2022-02-22	Priority-based scheduling is supported. You can use this feature to schedule pods to node pools based on priorities.
v1.20.4-ack-4.0	2021-09-02	Load-aware scheduling is supported. Elastic Container Instance-based scheduling is supported.
v1.20.4-ack-3.0	2021-05-26	Intelligent CPU scheduling based on sockets and L3 cache (last level cache) is supported.
v1.20.4-ack-2.0	2021-05-14	Capacity scheduling is supported.
v1.20.4-ack-1.0	2021-04-07	Intelligent CPU scheduling is supported. Coscheduling is supported. Topology-aware GPU scheduling is supported. GPU sharing is supported.

Release notes for V1.18

Version number	Release date	Description
v1.18-ack-4.0	2021-09-02	Load-aware scheduling is supported.
v1.18-ack-3.1	2021-06-05	Node pools are supported by Elastic Container Instance-based scheduling.
v1.18-ack-3.0	2021-03-12	Scheduling based on both Elastic Container Instance and Elastic Compute Service (ECS) is supported.
v1.18-ack-2.0	2020-11-30	Topology-aware GPU scheduling and GPU sharing are supported.
v1.18-ack-1.0	2020-09-24	Intelligent CPU scheduling and Coscheduling are supported.

Release notes for V1.16

Version number	Release date	Description
v1.16-ack-1.0	2020-07-21	Intelligent CPU scheduling is supported by clusters that run Kubernetes 1.16. Coscheduling is supported by clusters that run Kubernetes 1.16.