/sig scheduling

The satisfyExistingPodsAntiAffinity function unnecessarily iterates through all node labels when checking anti-affinity constraints:

Instead, iterate through existingAntiAffinityCounts directly:

  nodeLabels := nodeInfo.Node().Labels
  for tp, count := range state.existingAntiAffinityCounts {
      if count > 0 {
          if nodeValue, ok := nodeLabels[tp.key]; ok && nodeValue == tp.value {
              return false
          }
      }
  }

The performance difference depends on:

• Number of node labels (typically 10-15 on GKE, can be 20-30+ with custom labels)
• Number of entries in existingAntiAffinityCounts