View pricing for instance types on CoreWeave’s pricing page.
Availability
Node Pools are available in all General Access Regions.Node cordoning
CKS sometimes cordons Nodes to ensure that workloads are only scheduled to healthy Nodes. In most cases, CKS eventually removes the cordon, which makes the Node schedulable again. CoreWeave manages this kind of Node cordoning entirely, though you can also manually cordon Nodes for your own reasons.You can add your own Node conditions to the Nodes, but don’t use CoreWeave Node
conditions for automation. CoreWeave Node conditions are intended for internal use only, not for clients to use for their own custom management automation. CoreWeave can cordon Nodes for maintenance purposes or to resolve temporary issues.- Maintenance: If a Node requires maintenance, updates, or hardware fixes, CKS cordons it to ensure no new workloads are placed on it during that time. This lets the Node lifecycle controller make necessary changes without disrupting running tasks.
- Node draining for removal: If a Node must be removed from the cluster, CKS cordons the Node before draining it. CKS automatically reschedules workloads onto healthy Nodes, and no new workloads are scheduled to the cordoned Node.
- InfiniBand or Ethernet link flaps: Link flaps are intermittent, unpredictable up-down transitions in a network connection, which can result in networking or communication failures. If an InfiniBand or Ethernet link is flapping, a Node can experience inconsistent or unreliable connectivity. In this case, CKS cordons the Node to ensure no workloads are scheduled to a Node with an unreliable network connection.
- Temporary health check failures: Kubernetes uses health checks to assess the state of a user’s system. A temporary check failure might indicate transient issues that could degrade Node performance. CKS cordons the Node until the issue is resolved.
Node Pool prefill
Node Pool Prefill keeps a Node Pool at its target capacity while individual Nodes are replaced. When a Node is marked for triage (for example, for maintenance or a hardware issue, such as when thePendingPhaseState: triage condition is set), CKS provisions a replacement Node before the existing Node is drained and removed. The Node Pool stays at or above the number of Nodes specified in spec.targetNodes, so workloads do not see a capacity gap during the replacement window.
Prefill is opt in and off by default. Enable it for each Node Pool by adding a prefill block to the Node Pool spec. See Enable Node Pool prefill.
Prefill billingWhen you enable prefill, there are no billing implications.
When to use prefill
Use prefill for Node Pools whose workloads are sensitive to capacity loss during Node replacement, such as long-running training jobs or latency-sensitive inference.- Without prefill enabled: CKS replaces a Node only after the old Node is removed, so the Node Pool is below its target Node count until the replacement is delivered and ready. This leaves a capacity gap that can last 20 to 40 minutes.
- With prefill enabled: CKS provisions a replacement Node before the old Node is drained and removed, so the Node Pool stays at or above its target Node count throughout the replacement. Workloads keep running on the existing Node until the replacement is ready, which avoids a capacity gap during replacement.
Prefill availability
Prefill provisions replacement Nodes from on-demand capacity, so a replacement Node is not guaranteed. If on-demand capacity is unavailable, prefill keeps retrying, and the Node stays in the prefill flow until a replacement can be provisioned. Account for this when you rely on prefill for time-sensitive replacements.How prefill works
A Node is marked unschedulable as soon as it enters triage, so no new workloads are scheduled onto it. If a replacement Node can’t be provisioned, CKS keeps retrying until one is available or the Node is no longer marked for prefill. After the replacement is ready, CKS waits up to the idle timeout (spec.prefill.timeout) for the old Node to become idle, then removes it. If the Node hasn’t become idle when the timeout expires, CKS drains and replaces the Node.
Prefill Node conditions
When prefill is enabled, CKS sets aPrefill condition on Nodes that are in the prefill flow. The condition’s reason field indicates the current state. You can use LastTransitionTime on the condition to see when the reason last changed.
| Reason | Meaning |
|---|---|
AwaitingReplacement | The Node is marked for prefill and a replacement Node is being provisioned. |
AwaitingIdleTimeout | The replacement Node is in the cluster. CKS waits up to the idle timeout (spec.prefill.timeout) for this Node to become idle, then removes it. |
TimeoutExceeded | The Node did not become idle within the idle timeout (spec.prefill.timeout) period, so CKS drains and removes the Node. Monitor Nodes nearing their timeout period, so CKS doesn’t drain critical workloads. |
Prefill flow
The following diagram shows how a Node moves through the prefill flow, including the two paths CKS can take depending on whether the Node becomes idle within the default 24 hour idle timeout (spec.prefill.timeout) period.
For details on enabling prefill, see Enable Node Pool prefill. For the prefill reference specification, see Prefill reference.
Scaling strategies
The CKS cluster autoscaler has two possible scale-down strategies. Setspec.lifecycle.scaleDownStrategy to one of the following values:
| Strategy | Description |
|---|---|
IdleOnly | Default strategy. CKS only selects idle Nodes for removal. This strategy ensures that CKS only removes Nodes that aren’t actively running workloads. |
PreferIdle | CKS prioritizes idle Nodes for removal, but if there aren’t enough idle Nodes to meet the desired scale, CKS can also select non-idle Nodes. This allows faster scale-down when necessary. |
Idle Nodes
A Node is idle when it has no Pods in theRunning or Pending state. When determining a Node’s idle status, CKS ignores Pods with any of the following conditions:
| Condition | Description |
|---|---|
qos.coreweave.com/graceful-interruptible is set to true and the Pod’s DeletionGracePeriodSeconds has elapsed | CKS ignores graceful interruptible Pods only if they’re being deleted and the deletion grace period has elapsed. |
The Pod is part of a DaemonSet | CKS ignores Pods managed by a DaemonSet when determining Node idleness. |
qos.coreweave.cloud/interruptable label set to true | CKS ignores interruptible Pods when determining Node idleness. |
ns.coreweave.cloud/org label set to control-plane | CKS ignores Control Plane Pods when determining Node idleness. |
CWActive condition. CWActive = False means the Node is idle.
Node idle status and maintenance
CKS defers certain maintenance operations, such as moving a Node out of production after detecting elevated InfiniBand link flaps, until the Node becomes idle. A long-running Pod without an interruptible label keeps the Node active indefinitely, preventing those deferred operations from completing. For Pods that run continuously but can tolerate interruption, apply theqos.coreweave.cloud/interruptable or qos.coreweave.com/graceful-interruptible label so that CKS excludes the Pod from the Node’s idle calculation. See Pod interruption and eviction policies.
Once CKS selects a Node for removal, CKS removes the Node by first cordoning it to prevent any new Pods from being scheduled onto it. Then, CKS drains the Node to perform a graceful cleanup. Once the Node is fully drained, CKS removes it from the Node Pool.
DeletionGracePeriodSeconds defaults to 30 seconds unless the Pod’s spec.terminationGracePeriodSeconds is set to a different value.Scale down a Node Pool
To scale down a Node Pool:- Set
spec.targetNodesto the desired number of Nodes, orspec.targetRacks, depending on the target type set on the Node Pool. For instructions on doing this with Cloud Console or the Kubernetes CLI, see Manage Node Pools. - Set
spec.lifecycle.scaleDownStrategyto the preferred scaling strategy.
Node Pool types
CKS uses thedefault Node Pool type to manage Reserved and On-Demand instances. The following section describes when to use the default type and how to configure it.
Default Node Pools
CKS uses the default Node Pool type (spec.computeClass: default) for Reserved and On-Demand instances. Billing for default Node Pools depends on Reservation and utilization.
You don’t need to specify default Node Pools.If you don’t specify a
computeClass, the Node Pool defaults to the default type.Example default Node Pool manifest
Manage Node Pools with Terraform
The CoreWeave Terraform provider manages clusters, VPCs, and Object Storage, but it doesn’t include a Node Pool resource. Deploy Node Pools through the Cloud Console or the Kubernetes API instead. A Terraform-only workflow typically combines the CoreWeave provider for the cluster and VPC with a separate mechanism, such as the Kubernetes provider, to apply Node Pool manifests. See How do I use Terraform to manage clusters and Node Pools?.Image pull best practices
CoreWeave operates a region-level registry proxy that accelerates container image pulls and reduces exposure to public registry rate limits for your cluster’s Nodes. To ensure predictable and fast rollouts when scaling Node Pools, use immutable tags, or pin by digest, for production workloads. This ensures every Node pulls the same artifact and avoids stale results from proxy metadata caching. Avoid mutable tags like:latest. With metadata caching enabled, the proxy can continue serving a cached manifest until the cache expires, which can lead to inconsistent versions across Nodes. For more information, see the region-level image proxy documentation.
Reboot methods
You can manually reboot Nodes in the following two ways:| Reboot method | When to use | Typical duration |
|---|---|---|
| Reboot only | Maintenance, troubleshooting, or applying changes that don’t require reconfiguration | Approximately 10 minutes or more |
| Reconfigure reboot | Applying OS images, GPU driver updates, or other Node Pool modifications that require reconfiguration | Approximately 1 hour or more |
Node conditions for reboots (deprecated)
CoreWeave’s Node conditions are visible when you manage reboots. You previously set these Node conditions with the Conditioner Kubectl plugin, but you can now use the CoreWeave Intelligent CLI to reboot Nodes without Node conditions. See the Reboot Nodes and Apply Node Pool updates guides for more information.| Condition | Description | Deprecated equivalent |
|---|---|---|
AdminSafePowerCycle | Marks the Node to reboot when it is idle, only after all running jobs are complete. | AdminSafeReboot |
AdminImmediatePowerCycle | Marks the Node to reboot when it is idle, without waiting for running jobs to complete. | AdminImmediateReboot |
Control Plane Node Pool (deprecated)
CoreWeave provisioned clusters created before July 7, 2025 with acpu-control-plane Node Pool for CKS-managed components. Clusters created after this date don’t have this Node Pool. The CKS Control Plane now manages the components out-of-band. See the Control Plane Node Pool release notes for more information.