udp/congestion/newreno.go

@@ -147,7 +147,7 @@ func (c *NewReno) receivedSequence(seq uint32) {
 	c.ackNackMu.Lock()
 	defer c.ackNackMu.Unlock()
 
-	if !(c.ack != seq-1 && c.nack != seq-1) {
+	if c.ack != seq-1 && c.nack != seq-1 {
 		c.awaitingAck = append(c.awaitingAck, flightInfo{
 			time:     time.Now(),
 			sequence: seq,
@@ -155,10 +155,8 @@ func (c *NewReno) receivedSequence(seq uint32) {
 		return // if this seq doesn't change the ack field, awaitingAck will be unchanged
 	}
 
-	c.ack = seq
 	sort.Sort(c.awaitingAck)
-
-	a := c.ack
+	a := seq
 
 	var i int
 	var e flightInfo

udp/congestion/newreno_test.go

@@ -63,6 +63,7 @@ func (n *newRenoTest) RunSideA(ctx context.Context) {
 			case <-ctx.Done():
 				return
 			case p := <-n.aInbound:
+				fmt.Printf("side A received: %d,%d,%d\n", p.seq, p.nack, p.ack)
 				n.sideA.ReceivedPacket(p.seq, p.nack, p.ack)
 			}
 		}
@@ -75,11 +76,11 @@ func (n *newRenoTest) RunSideA(ctx context.Context) {
 			}
 
 			seq := n.sideA.AwaitEarlyUpdate(500 * time.Millisecond)
-			if seq != 0 {
+			if seq == 0 { // discard keepalives
 				p := congestionPacket{
 					seq:  seq,
-					nack: n.sideA.NextAck(),
-					ack:  n.sideA.NextNack(),
+					nack: n.sideA.NextNack(),
+					ack:  n.sideA.NextAck(),
 				}
 				n.aOutbound <- p
 			}
@@ -94,6 +95,7 @@ func (n *newRenoTest) RunSideB(ctx context.Context) {
 			case <-ctx.Done():
 				return
 			case p := <-n.bInbound:
+				fmt.Printf("side B received: %d,%d,%d\n", p.seq, p.nack, p.ack)
 				n.sideB.ReceivedPacket(p.seq, p.nack, p.ack)
 			}
 		}
@@ -106,11 +108,11 @@ func (n *newRenoTest) RunSideB(ctx context.Context) {
 			}
 
 			seq := n.sideB.AwaitEarlyUpdate(500 * time.Millisecond)
-			if seq != 0 {
+			if seq == 0 { // discard keepalives
 				p := congestionPacket{
 					seq:  seq,
-					nack: n.sideB.NextAck(),
-					ack:  n.sideB.NextNack(),
+					nack: n.sideB.NextNack(),
+					ack:  n.sideB.NextAck(),
 				}
 				n.bOutbound <- p
 			}