### Feature

- Add flag --lease-max-object-size and metric etcd_lease_object_counts for kube-apiserver to config and observe max objects attached to a single etcd lease. ([#97480](https://github.com/kubernetes/kubernetes/pull/97480), [@lingsamuel](https://github.com/lingsamuel)) [SIG API Machinery, Instrumentation and Scalability]

- Enable cAdvisor ProcessMetrics collecting. ([#79002](https://github.com/kubernetes/kubernetes/pull/79002), [@jiayingz](https://github.com/jiayingz))
- kubelet: change `node-lease-renew-interval` to 0.25 of lease-renew-duration ([#80429](https://github.com/kubernetes/kubernetes/pull/80429), [@gaorong](https://github.com/gaorong))

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  linking directly to the master branch. This ensures that links reference a
  specific point in time, rather than a document that may change over time.
  
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- 'Promoted the `APIServerIdentity` feature to Beta. By default, each `kube-apiserver`
  will now create a Lease in the `kube-system` namespace. These lease objects can
  be used to identify the number of active API servers in the cluster, and may also
  be used for future features such as the Storage Version API.'

 - Kubeadm: the flag `--cri-socket` is no longer allowed in a mixture with the flag `--config`. Please use the kubeadm configuration for setting the CRI socket for...

// https://www.iana.org/domains/root/db/lawyer.html
lawyer

// lds : IRI Domain Management, LLC
// https://www.iana.org/domains/root/db/lds.html
lds

// lease : Binky Moon, LLC
// https://www.iana.org/domains/root/db/lease.html
lease

// leclerc : A.C.D. LEC Association des Centres Distributeurs Edouard Leclerc
// https://www.iana.org/domains/root/db/leclerc.html
leclerc

  KEPs or supporting documentation, please reference a specific commit and avoid
  linking directly to the master branch. This ensures that links reference a
  specific point in time, rather than a document that may change over time.
  
  See here for guidance on getting permanent links to files: https://help.github.com/en/articles/getting-permanent-links-to-files
  
  Please use the following format for linking documentation:

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lawyer
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lcube-server.de
lds
le.it
leadpages.co
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lebesby.no
lebork.pl
lebtimnetz.de
lecce.it
lecco.it
leclerc
leczna.pl
lefrak
leg.br
legal
legnica.pl
lego
leikanger.no

- The `v1` version of `LeaderMigrationConfiguration` supports only `leases` API for leader election. To use formerly supported mechanisms, please continue using `v1beta1`. ([#108016](https://github.com/kubernetes/kubernetes/pull/108016), [@jiahuif](https://github.com/jiahuif))

    try {
      insert(e);
    } finally {
      monitor.leave();
    }
  }

  @CanIgnoreReturnValue
  @Override
  public @Nullable E poll() {
    Monitor monitor = this.monitor;
    if (monitor.enterIf(notEmpty)) {
      try {
        return extract();
      } finally {
        monitor.leave();
      }
    } else {
      return null;
    }
  }