### SIG Scheduling

scalability testing in a continuous integration (CI) environment. The SIG
defined a concrete process for scalability testing, created
documentation for the current scalability thresholds, and defined a new set of
Service Level Indicators (SLIs) and Service Level Objectives (SLOs) for the system.
Here's the release [scalability validation report].

[SIG Scalability]: https://github.com/kubernetes/community/tree/master/sig-scalability

Rawat, Astropeak, Ayush Agrawal, Bairen Yi, Bas Aarts, Bastian Eichenberger, Ben
Barsdell, Benjamin Peterson, bhack, Bharat Raghunathan, Bhavani Subramanian,
Bryan Cutler, candy.dc, Cao Zongyan, Captain-Pool, Casper Da Costa-Luis, Chen
Guoyin, Cheng Chang, chengchingwen, Chong Yan, Choong Yin Thong, Christopher
Yeh, Clayne Robison, Coady, Patrick, Dan Ganea, David Norman, Denis Khalikov,

- Kubeadm: fix panic when no UpgradeConfiguration was found in the config file ([#130312](https://github.com/kubernetes/kubernetes/pull/130312), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]
- Makes kubelet's /metrics/slis endpoint always available ([#130084](https://github.com/kubernetes/kubernetes/pull/130084), [@richabanker](https://github.com/richabanker)) [SIG Architecture, Instrumentation and Node]

## Changelog since v1.28.6

## Changes by Kind

### Feature

- Add process_start_time_seconds to /metrics/slis endpoint of all components ([#122750](https://github.com/kubernetes/kubernetes/pull/122750), [@richabanker](https://github.com/richabanker)) [SIG Architecture, Instrumentation and Testing]
- Kubernetes is now built with go 1.21.7

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