- [Quality of Service for memory resources](#quality-of-service-for-memory-resources)
    - [API changes and improvements for ephemeral containers](#api-changes-and-improvements-for-ephemeral-containers)
  - [Known Issues](#known-issues)

  // Must be an empty string (default) or Memory.
  // More info: https://kubernetes.io/docs/concepts/storage/volumes#emptydir
  // +optional
  optional string medium = 1;

  // sizeLimit is the total amount of local storage required for this EmptyDir volume.
  // The size limit is also applicable for memory medium.
  // The maximum usage on memory medium EmptyDir would be the minimum value between

* Fixes a bug where kubelet crashes trying to free memory under memory pressure. ([#58574](https://github.com/kubernetes/kubernetes/pull/58574), [@yastij](https://github.com/yastij))

  - The disk-cached discovery client is moved from k8s.io/client-go/discovery to k8s.io/client-go/discovery/cached/disk.
The memory-cached discovery client is moved from k8s.io/client-go/discovery/cached to k8s.io/client-go/discovery/cached/memory.
([#72214](https://github.com/kubernetes/kubernetes/pull/72214), [@caesarxuchao](https://github.com/caesarxuchao))

- kubeadm

- Kubernetes will try to acquire the iptables lock every 100 msec during 5 seconds instead of every second. This is especially useful for environments using kube-proxy in iptables mode with a high churn rate of services. ([#85771](https://github.com/kubernetes/kubernetes/pull/85771), [@aojea](https://github.com/aojea)) [SIG...

- Fixes a kubelet and kube-apiserver memory leak in default 1.29 configurations related to tracing. ([#126985](https://github.com/kubernetes/kubernetes/pull/126985), [@dashpole](https://github.com/dashpole)) [SIG API Machinery and Node]

  Burstable QoS pods. For Best-Effort/Guaranteed QoS pods, swap would be disabled.
  
  Containers with memory requests equal to their memory limits also won't have
  swap access, and it is a way to opt-out of swap for a single container.
  
  The formula for the swap limit for Burstable QoS pods is:
  `(<memory-request>/<node-memory-capacity>)*<node-swap-capacity>`.
  

* Check if container memory stats are available before accessing it ([#77656](https://github.com/kubernetes/kubernetes/pull/77656), [@yastij](https://github.com/yastij))

### Non-recursive Volume Ownership (FSGroup) graduates to Beta

By default, the `fsgroup` setting, if specified, recursively updates permissions for every file in a volume on every mount. This can make mount, and pod startup, very slow if the volume has many files. 

- Fix memory leak in kube-apiserver when underlying time goes forth and back. ([#96266](https://github.com/kubernetes/kubernetes/pull/96266), [@chenyw1990](https://github.com/chenyw1990)) [SIG API Machinery]