- The client label for apiserver_request_count and apiserver_request_total now no-opts and merely records an empty string. ([#87673](https://github.com/kubernetes/kubernetes/pull/87673), [@logicalhan](https://github.com/logicalhan)) [SIG API Machinery, Instrumentation and Scalability]


<!-- NEW RELEASE NOTES ENTRY -->


# v1.15.9

    /** The key of the configuration. e.g. 200 */
    String RANK_FUSION_window_size = "rank.fusion.window_size";

    /** The key of the configuration. e.g. 20 */
    String RANK_FUSION_rank_constant = "rank.fusion.rank_constant";

    /** The key of the configuration. e.g. -1 */
    String RANK_FUSION_THREADS = "rank.fusion.threads";

    /** The key of the configuration. e.g. rf_score */

- In the API Priority and Fairness feature, priority levels that are exempt from limitation can now be given a nominal and a lendable concurrency and their dispatching borrows from the concurrency limits of the other...

- `kubeadm init` and `kubeadm init phase` now have a `--image-repository` flag, improving support for environments with limited access to official kubernetes repository.
- The DynamicKubeletConfig and SelfHosting functionality was moved outside of `kubeadm init` and feature gates and is now exposed under `kubeadm alpha`.

- Deprecated the `apiserver_request_slo_duration_seconds` metric for v1.27 in favor of `apiserver_request_sli_duration_seconds` for naming consistency purposes with other SLI-specific metrics and to avoid any confusion between SLOs and SLIs. ([#112679](https://github.com/kubernetes/kubernetes/pull/112679), [@dgrisonnet](https://github.com/dgrisonnet))

- Kubernetes is now built with Go 1.19.6 ([#115832](https://github.com/kubernetes/kubernetes/pull/115832), [@cpanato](https://github.com/cpanato)) [SIG Release and Testing]

### Bug or Regression