Function TestConsistentHashKeyDistribution

loadbalancer/algorithm_test.go:462–475

(t *testing.T)

}

func TestConsistentHashKeyDistribution(t *testing.T) {
	endpoints := []string{"http://10.2.0.1:8080", "http://10.2.0.2:8080", "http://10.2.0.3:8080", "http://10.2.0.4:8080", "http://10.2.0.5:8080", "http://10.2.0.6:8080", "http://10.2.0.7:8080", "http://10.2.0.8:8080", "http://10.2.0.9:8080", "http://10.2.0.10:8080"}

	stdDev1hashPerEndpoint := measureStdDev(endpoints, 1)
	stdDev100HashesPerEndpoint := measureStdDev(endpoints, 100)

	if stdDev100HashesPerEndpoint >= stdDev1hashPerEndpoint {
		t.Errorf("Standard deviation with 100 hashes per endpoint should be lower than with 1 hash per endpoint. 100 hashes: %f, 1 hash: %f", stdDev100HashesPerEndpoint, stdDev1hashPerEndpoint)
	}

	if stdDev100HashesPerEndpoint >= 10 { // arbitrary target to flag accidental breaking changes. Currently is 5.93
		t.Errorf("Standard deviation was too high for 100 vnodes, got %f", stdDev100HashesPerEndpoint)
	}
}

func addInflightRequests(registry *routing.EndpointRegistry, endpoint routing.LBEndpoint, count int) {
	for i := 0; i < count; i++ {