Lighthouse handler optimizations (#320)

We noticed that the number of memory allocations LightHouse.HandleRequest creates for each call can seriously impact performance for high traffic lighthouses. This PR introduces a benchmark in the first commit and then optimizes memory usage by creating a LightHouseHandler struct. This struct allows us to re-use memory between each lighthouse request (one instance per UDP listener go-routine).

lighthouse_test.go

@@ -36,12 +36,19 @@ func TestNewipandportfromudpaddr(t *testing.T) {
 	assert.Equal(t, uint32(12345), meh.Port)
 }
 
-func TestNewipandportsfromudpaddrs(t *testing.T) {
+func TestSetipandportsfromudpaddrs(t *testing.T) {
 	blah := NewUDPAddrFromString("1.2.2.3:12345")
 	blah2 := NewUDPAddrFromString("9.9.9.9:47828")
 	group := []udpAddr{*blah, *blah2}
-	hah := NewIpAndPortsFromNetIps(group)
-	assert.IsType(t, &[]*IpAndPort{}, hah)
+	var lh *LightHouse
+	lhh := lh.NewRequestHandler()
+	result := lhh.setIpAndPortsFromNetIps(group)
+	assert.IsType(t, []*IpAndPort{}, result)
+	assert.Len(t, result, 2)
+	assert.Equal(t, uint32(0x01020203), result[0].Ip)
+	assert.Equal(t, uint32(12345), result[0].Port)
+	assert.Equal(t, uint32(0x09090909), result[1].Ip)
+	assert.Equal(t, uint32(47828), result[1].Port)
 	//t.Error(reflect.TypeOf(hah))
 
 }
@@ -66,6 +73,57 @@ func Test_lhStaticMapping(t *testing.T) {
 	assert.EqualError(t, err, "Lighthouse 10.128.0.3 does not have a static_host_map entry")
 }
 
+func BenchmarkLighthouseHandleRequest(b *testing.B) {
+	lh1 := "10.128.0.2"
+	lh1IP := net.ParseIP(lh1)
+
+	udpServer, _ := NewListener("0.0.0.0", 0, true)
+
+	lh := NewLightHouse(true, 1, []uint32{ip2int(lh1IP)}, 10, 10003, udpServer, false, 1, false)
+
+	hAddr := NewUDPAddrFromString("4.5.6.7:12345")
+	hAddr2 := NewUDPAddrFromString("4.5.6.7:12346")
+	lh.addrMap[3] = []udpAddr{*hAddr, *hAddr2}
+
+	rAddr := NewUDPAddrFromString("1.2.2.3:12345")
+	rAddr2 := NewUDPAddrFromString("1.2.2.3:12346")
+	lh.addrMap[2] = []udpAddr{*rAddr, *rAddr2}
+
+	mw := &mockEncWriter{}
+
+	b.Run("notfound", func(b *testing.B) {
+		lhh := lh.NewRequestHandler()
+		req := &NebulaMeta{
+			Type: NebulaMeta_HostQuery,
+			Details: &NebulaMetaDetails{
+				VpnIp:      4,
+				IpAndPorts: nil,
+			},
+		}
+		p, err := proto.Marshal(req)
+		assert.NoError(b, err)
+		for n := 0; n < b.N; n++ {
+			lhh.HandleRequest(rAddr, 2, p, nil, mw)
+		}
+	})
+	b.Run("found", func(b *testing.B) {
+		lhh := lh.NewRequestHandler()
+		req := &NebulaMeta{
+			Type: NebulaMeta_HostQuery,
+			Details: &NebulaMetaDetails{
+				VpnIp:      3,
+				IpAndPorts: nil,
+			},
+		}
+		p, err := proto.Marshal(req)
+		assert.NoError(b, err)
+
+		for n := 0; n < b.N; n++ {
+			lhh.HandleRequest(rAddr, 2, p, nil, mw)
+		}
+	})
+}
+
 //func NewLightHouse(amLighthouse bool, myIp uint32, ips []string, interval int, nebulaPort int, pc *udpConn, punchBack bool) *LightHouse {
 
 /*