Kubernetes 1.35 "Timbernetes": in-place pod resize reaches stable

2025-12-17 · Publisher : Kubernetes · Domain : Cloud & DevOps

On 17 December 2025, Kubernetes 1.35 ships 60 enhancements (17 stable). In-place pod resize reaches stable, cgroup v1 is removed, ipvs is deprecated and it is the last version supporting containerd 1.x.

### Background On 17 December 2025, Kubernetes releases version **1.35 "Timbernetes"**: **60 enhancements**, including 17 stable, 19 beta and 22 alpha. The headline update is the general availability of **in-place pod resource resizing**: CPU and memory change without restarting the pod or its containers. ### Key facts - In-place resize (KEP-1287): alpha in 1.27, beta in 1.33, stable in 1.35, after more than six years of design. - Pod certificates in beta: the kubelet generates keys and requests certificates to provide workload identity, without going through cert-manager or SPIFFE/SPIRE. - Other stable graduations: the Job `managedBy` field (useful for MultiKueue), kubelet configuration drop-in directory, fine-grained supplemental groups control. - **Removal of cgroup v1 support**: nodes on older Linux distributions must move to cgroup v2; kube-proxy's **ipvs** mode is deprecated. - 1.35 is the **last version to support containerd 1.x**: you must move to containerd 2.0 or later before the next one. ### Why it matters In-place resizing answers a long-standing need of databases, batch jobs and inference: adjusting resources without interrupting service. It also feeds vertical autoscaling. For operators, the release is mostly about inventory: nodes on cgroup v1, kube-proxy on ipvs, containerd 1.x, all prerequisites to handle before the 2026 upgrades. The post also notes better pod stability across kubelet restarts: existing containers' state is restored from the runtime. ### Takeaway Kubernetes 1.35 makes pod resizing without restart production-ready, and sets migration deadlines.

Tags : Kubernetes, Cloud natif, Conteneurs, FinOps, Open Source