s1.DifferenceInPlace(s2)
		}
	})
	b.Run("Intersection", func(b *testing.B) {
		for i := 0; i < b.N; i++ {
			s1.Intersection(s2)
		}
	})
	b.Run("IntersectInPlace", func(b *testing.B) {
		for i := 0; i < b.N; i++ {
			s1.IntersectInPlace(s2)
		}
	})

	result := New[T]()
	for key := range s {
		if s2.Contains(key) {
			result.Insert(key)
		}
	}
	return result
}

// IntersectInPlace similar to Intersection, but has better performance.
// Note: This function modifies s in place.
func (s Set[T]) IntersectInPlace(s2 Set[T]) Set[T] {
	for key := range s {
		if !s2.Contains(key) {
			delete(s, key)
		}
	}
	return s
}

			addresses = updatedAddresses
		} else {
			// this is from the external triggers instead of request
			// send response for all the subscribed intersect with the updated
			addresses = updatedAddresses.IntersectInPlace(subs)
		}
	}

	if !w.Wildcard {
		// We only need this for on-demand. This allows us to subscribe the client to resources they
		// didn't explicitly request.

	touchedNamespaceLabels.InsertAll(getLabelKeys(newNs)...)

	// Next, we find all keys our Gateways actually reference.
	c.stateMu.RLock()
	intersection := touchedNamespaceLabels.IntersectInPlace(c.state.ReferencedNamespaceKeys)
	c.stateMu.RUnlock()

	// If there was any overlap, then a relevant namespace label may have changed, and we trigger a