p2p/discv5: add egress/ingress traffic metrics to discv5 udp transport (

ethereum#16369)

p2p/discv5/metrics.go

@@ -0,0 +1,8 @@
+package discv5
+
+import "github.com/ethereum/go-ethereum/metrics"
+
+var (
+ ingressTrafficMeter = metrics.NewRegisteredMeter("discv5/InboundTraffic", nil)
+ egressTrafficMeter = metrics.NewRegisteredMeter("discv5/OutboundTraffic", nil)
+)

p2p/discv5/udp.go

@@ -334,8 +334,10 @@ func (t *udp) sendPacket(toid NodeID, toaddr *net.UDPAddr, ptype byte, req inter
  return hash, err
  }
  log.Trace(fmt.Sprintf(">>> %v to %x@%v", nodeEvent(ptype), toid[:8], toaddr))
- if _, err = t.conn.WriteToUDP(packet, toaddr); err != nil {
+ if nbytes, err := t.conn.WriteToUDP(packet, toaddr); err != nil {
  log.Trace(fmt.Sprint("UDP send failed:", err))
+ } else {
+ egressTrafficMeter.Mark(int64(nbytes))
  }
  //fmt.Println(err)
  return hash, err
@@ -374,6 +376,7 @@ func (t *udp) readLoop() {
  buf := make([]byte, 1280)
  for {
  nbytes, from, err := t.conn.ReadFromUDP(buf)
+ ingressTrafficMeter.Mark(int64(nbytes))
  if netutil.IsTemporaryError(err) {
  // Ignore temporary read errors.
  log.Debug(fmt.Sprintf("Temporary read error: %v", err))