* Fixing heapster memory requirements. ([#26109](https://github.com/kubernetes/kubernetes/pull/26109), [@Q-Lee](https://github.com/Q-Lee))
* Handle federated service name lookups in kube-dns. ([#25727](https://github.com/kubernetes/kubernetes/pull/25727), [@madhusudancs](https://github.com/madhusudancs))

            case NtStatus.NT_STATUS_OBJECT_NAME_NOT_FOUND:
            case NtStatus.NT_STATUS_OBJECT_PATH_NOT_FOUND:
                // Cache negative results to avoid repeated failed lookups
                this.attrExpiration = currentTime + getContext().getConfig().getAttributeCacheTimeout();
                return false;
            default:
                throw se;
            }

- Changed Job controller to use the controller UID index for Pod lookups to improve performance. ([#132305](https://github.com/kubernetes/kubernetes/pull/132305), [@xigang](https://github.com/xigang))

- Hostnames are now converted to lowercase before being used for node lookups in the kubernetes-worker charm. ([#65487](https://github.com/kubernetes/kubernetes/pull/65487), [@dshcherb](https://github.com/dshcherb))

### Internal

* ♻ Refactor dict value extraction to minimize key lookups `fastapi/utils.py`. PR [#3139](https://github.com/tiangolo/fastapi/pull/3139) by [@ShahriyarR](https://github.com/ShahriyarR).