c.Close()
		}()
	}
	wg.Wait()
	dss.teardown()
	after := sw.Sockets()
	if len(after) != len(before) {
		t.Errorf("got %d; want %d", len(after), len(before))
	}
}

// Define a pair of blackholed (IPv4, IPv6) addresses, for which dialTCP is
// expected to hang until the timeout elapses. These addresses are reserved
// for benchmarking by RFC 6890.
const (
	slowDst4 = "198.18.0.254"
	slowDst6 = "2001:2::254"

			}
		})
	}
}

var (
	blackhole []byte
)

func BenchmarkAppendSliceLarge(b *testing.B) {
	for _, length := range []int{1 << 10, 4 << 10, 16 << 10, 64 << 10, 256 << 10, 1024 << 10} {
		y := make([]byte, length)
		b.Run(fmt.Sprint(length, "Bytes"), func(b *testing.B) {
			for i := 0; i < b.N; i++ {
				blackhole = nil
				blackhole = append(blackhole, y...)
			}
		})
	}
}

		port = service.Ports[0].Port

		// Do not return blackhole cluster for service==nil case as there is a legitimate use case for
		// calling this function with nil service: to route to a pre-defined statically configured cluster
		// declared as part of the bootstrap.
		// If blackhole cluster is needed, do the check on the caller side. See gateway and tls.go for examples.
	}

func RunExternalRequest(t *testing.T, cases []*TestCase, prometheus prometheus.Instance, mode TrafficPolicy) {
	t.Helper()
	// Testing of Blackhole and Passthrough clusters:
	// Setup of environment:
	// 1. client and destination are deployed to app-1-XXXX namespace

		// has multiple ports, then route to a cluster with the listener port (i.e. sidecar defined port) - the
		// traffic will most likely blackhole.
		port := listenPort.Port
		if len(service.Ports) == 1 {
			port = service.Ports[0].Port
		}

		clusterName := model.BuildSubsetKey(model.TrafficDirectionOutbound, "", service.Hostname, port)

					},
					Result: simulation.Result{
						Error:              simulation.ErrNoRoute,
						ListenerMatched:    "0.0.0.0_80",
						RouteConfigMatched: "http.80",
						VirtualHostMatched: "blackhole:80",
					},
				},
				{
					// There will be no listener
					Name: "undefined port",
					Call: simulation.Call{
						Port:       81,
						HostHeader: "foo.bar",

)

const (
	// BlackHoleCluster to catch traffic from routes with unresolved clusters. Traffic arriving here goes nowhere.
	BlackHoleCluster = "BlackHoleCluster"
	// BlackHole is the name of the virtual host and route name used to block all traffic
	BlackHole = "block_all"
	// PassthroughCluster to forward traffic to the original destination requested. This cluster is used when
	// traffic does not match any listener in envoy.

					},
				},
			},
			IncludeRequestAttemptCount: includeRequestAttemptCount,
		}
	}

	return &route.VirtualHost{
		Name:    util.BlackHole,
		Domains: []string{"*"},
		Routes: []*route.Route{
			{
				Name: util.BlackHole,
				Match: &route.RouteMatch{
					PathSpecifier: &route.RouteMatch_Prefix{Prefix: "/"},
				},
				Action: &route.Route_DirectResponse{

	}

	// Expect 9 CDS clusters:
	// 2 inbound(http, inbound passthroughipv4) notes: no passthroughipv6
	// 9 outbound (2 http services, 1 tcp service,
	//   and 2 subsets of http1, 1 blackhole, 1 passthrough)
	if (len(adsc.GetClusters()) + len(adsc.GetEdsClusters())) != 9 {
		t.Fatalf("Expected 9 clusters in CDS output. Got %d", len(adsc.GetClusters())+len(adsc.GetEdsClusters()))
	}

	// Make sure it doesn't change between patches
	if d := cmp.Diff(l1, l2, protocmp.Transform()); d != "" {
		t.Fatal(d)
	}
	// Make sure we have exactly 1 access log
	fc := xdstest.ExtractFilterChain("virtualOutbound-blackhole", xdstest.ExtractListener("virtualOutbound", l1))
	if len(xdstest.ExtractTCPProxy(t, fc).GetAccessLog()) != 1 {
		t.Fatalf("unexpected access log: %v", xdstest.ExtractTCPProxy(t, fc).GetAccessLog())
	}
}