- Calculated pod resources are now cached when adding pods to NodeInfo in the scheduler framework, improving performance when processing unschedulable pods. ([#129635](https://github.com/kubernetes/kubernetes/pull/129635), [@macsko](https://github.com/macsko)) [SIG Scheduling]

# Linux x86 so that we can use RBE. Since tests still need to run on the single
# host Arm64 machine, the build becomes too slow (~30 min) to be a presubmit.
# For testing purposes, we want to see the runtime performance of an
# experimental job that is build-only, i.e, we only build the test targets and
# do not run them. By prefixing the configs with "build", we can run both

      return result;
    } else {
      return new RegularImmutableSortedSet<>(ImmutableList.of(), comparator);
    }
  }

  /**
   * Returns the empty immutable sorted set.
   *
   * <p><b>Performance note:</b> the instance returned is a singleton.
   */
  @SuppressWarnings("unchecked") // The natural-ordered empty set supports all types.
  public static <E> ImmutableSortedSet<E> of() {

</p>

<p>
Reads of memory locations larger than a single machine word
are encouraged but not required to meet the same semantics
as word-sized memory locations,
observing a single allowed write <i>w</i>.
For performance reasons,
implementations may instead treat larger operations
as a set of individual machine-word-sized operations
in an unspecified order.
This means that races on multiword data structures

## Changelog since v1.28.10

## Changes by Kind

### API Change

- Improved scheduling performance when many nodes, and prefilter returns 1-2 nodes (e.g. daemonset)
  

### Node

SIG Node iterated on the ability to support more workloads with better performance and improved reliability.  Alpha features were improved around hardware accelerator support, device plugins enablement, and cpu pinning policies to enable us to graduate these features to beta in a future release.  In addition, a number of reliability and performance enhancements were made across the node to help operators in production.

### OpenStack

  
  As this code is still very new, it has not been heavily optimized yet;
  while it is expected to _eventually_ have better performance than the
  iptables backend, very little performance testing has been done so far. ([#121046](https://github.com/kubernetes/kubernetes/pull/121046), [@danwinship](https://github.com/danwinship))

* Resolves bottleneck in internal API server communication that can cause increased goroutines and degrade API Server performance ([#80465](https://github.com/kubernetes/kubernetes/pull/80465), [@answer1991](https://github.com/answer1991))

 * addressed by the new {@link java.util.stream.Stream} library. Read the method documentation below
 * for comparisons. This class is not being deprecated, but we gently encourage you to migrate to
 * streams.
 *
 * <p><i>Performance notes:</i> Unless otherwise noted, all of the iterables produced in this class
 * are <i>lazy</i>, which means that their iterators only advance the backing iteration when
 * absolutely necessary.
 *

- Kubectl create service now respects namespace flag ([#101005](https://github.com/kubernetes/kubernetes/pull/101005), [@zxh326](https://github.com/zxh326)) [SIG CLI]
- Kubelet: improve the performance when waiting for a synchronization of the node list with the kube-apiserver ([#99336](https://github.com/kubernetes/kubernetes/pull/99336), [@neolit123](https://github.com/neolit123)) [SIG Node]