- Fixed keymutex issues which may crash in some platforms. ([#74348](https://github.com/kubernetes/kubernetes/pull/74348), [@danielqsj](https://github.com/danielqsj))
- Considerably reduced the CPU load in kube-apiserver while aggregating OpenAPI specifications from aggregated API servers. ([#71223](https://github.com/kubernetes/kubernetes/pull/71223), [@sttts](https://github.com/sttts))

		duration := max(time.Duration(r.Float64()*float64(time.Minute)),
			// Make sure to sleep at least a second to avoid high CPU ticks.
			time.Second)
		time.Sleep(duration)
	}
	c.RLock()
	defer c.RUnlock()
	if c.enabled {
		logger.Info("Cluster replication initialized")
	}
	return nil
}

- Fixed an error when trying to expand a volume that does not require node expansion. ([#123055](https://github.com/kubernetes/kubernetes/pull/123055), [@gnufied](https://github.com/gnufied))
- Fixed an issue calculating total CPU usage reported for Windows nodes. ([#122999](https://github.com/kubernetes/kubernetes/pull/122999), [@marosset](https://github.com/marosset))

- Added Service Account field in the output of `kubectl describe pod` command. ([#111192](https://github.com/kubernetes/kubernetes/pull/111192), [@aufarg](https://github.com/aufarg))
- Added a new `align-by-socket` policy option to cpu manager `static` policy.  When enabled CPU's to be aligned at socket boundary rather than NUMA boundary. ([#111278](https://github.com/kubernetes/kubernetes/pull/111278), [@arpitsardhana](https://github.com/arpitsardhana))

- Fix a race in the timeout handler that could lead to kube-apiserver crashes ([#108455](https://github.com/kubernetes/kubernetes/pull/108455), [@Argh4k](https://github.com/Argh4k))
- Fix container creation errors for pods with cpu requests bigger than 256 cpus ([#106570](https://github.com/kubernetes/kubernetes/pull/106570), [@odinuge](https://github.com/odinuge))

- The `kubectl top` command now includes a `--sort-by` option to sort by `memory` or `cpu`. ([#75920](https://github.com/kubernetes/kubernetes/pull/75920), [@artmello](https://github.com/artmello))

* Cluster Autoscaler - fixes issues with taints and updates kube-proxy cpu request. ([#50514](https://github.com/kubernetes/kubernetes/pull/50514), [@mwielgus](https://github.com/mwielgus))

    * This solves a vulnerability that could allow denial of service attacks by using many small multipart fields/files (parts), consuming high CPU and memory.
    * Only applications using forms (e.g. file uploads) could be affected.
    * For most cases, upgrading won't have any breaking changes.

## 0.91.0

### Upgrades