Function TestConsistentHashBoundedLoadDistribution

loadbalancer/algorithm_test.go:420–460

(t *testing.T)

}

func TestConsistentHashBoundedLoadDistribution(t *testing.T) {
	endpoints := []string{"http://127.0.0.1:8080", "http://127.0.0.2:8080", "http://127.0.0.3:8080"}
	r, _ := http.NewRequest("GET", "http://127.0.0.1:1234/foo", nil)
	route := NewAlgorithmProvider().Do([]*routing.Route{{
		Route: eskip.Route{
			BackendType: eskip.LBBackend,
			LBAlgorithm: ConsistentHash.String(),
			LBEndpoints: eskip.NewLBEndpoints(endpoints),
		},
	}})[0]

	ch := route.LBAlgorithm.(*consistentHash)
	balanceFactor := 1.25
	ctx := &routing.LBContext{
		Request:     r,
		Route:       route,
		LBEndpoints: route.LBEndpoints,
		Params:      map[string]interface{}{ConsistentHashBalanceFactor: balanceFactor},
	}
	endpointRegistry := routing.NewEndpointRegistry(routing.RegistryOptions{})
	defer endpointRegistry.Close()
	endpointRegistry.Do([]*routing.Route{route})

	for i := 0; i < 100; i++ {
		ep := ch.Apply(ctx)
		ifr0 := route.LBEndpoints[0].Metrics.InflightRequests()
		ifr1 := route.LBEndpoints[1].Metrics.InflightRequests()
		ifr2 := route.LBEndpoints[2].Metrics.InflightRequests()

		assert.Equal(t, int64(ifr0), endpointRegistry.GetMetrics(route.LBEndpoints[0].Host).InflightRequests())
		assert.Equal(t, int64(ifr1), endpointRegistry.GetMetrics(route.LBEndpoints[1].Host).InflightRequests())
		assert.Equal(t, int64(ifr2), endpointRegistry.GetMetrics(route.LBEndpoints[2].Host).InflightRequests())

		avg := float64(ifr0+ifr1+ifr2) / 3.0
		limit := int64(avg*balanceFactor) + 1
		if ifr0 > limit || ifr1 > limit || ifr2 > limit {
			t.Errorf("Expected in-flight requests for each endpoint to be less than %d. In-flight request counts: %d, %d, %d", limit, ifr0, ifr1, ifr2)
		}
		endpointRegistry.GetMetrics(ep.Host).IncInflightRequest()
	}
}

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"}