From abe8da697c7737bfe7aca45fba10f621506fad1d Mon Sep 17 00:00:00 2001
From: Pascal Fischer <32096965+pascal-fischer@users.noreply.github.com>
Date: Mon, 17 Feb 2025 17:07:30 +0100
Subject: [PATCH] [signal] add pprof and message size metrics (#3337)

---
 signal/cmd/run.go       | 13 +++++++++++++
 signal/metrics/app.go   | 29 +++++++++++++++++++++++++++++
 signal/server/signal.go |  2 ++
 3 files changed, 44 insertions(+)

diff --git a/signal/cmd/run.go b/signal/cmd/run.go
index 1bb2f1d0c..3a671a848 100644
--- a/signal/cmd/run.go
+++ b/signal/cmd/run.go
@@ -8,6 +8,8 @@ import (
 	"fmt"
 	"net"
 	"net/http"
+	// nolint:gosec
+	_ "net/http/pprof"
 	"strings"
 	"time"
 
@@ -82,6 +84,8 @@ var (
 		RunE: func(cmd *cobra.Command, args []string) error {
 			flag.Parse()
 
+			startPprof()
+
 			opts, certManager, err := getTLSConfigurations()
 			if err != nil {
 				return err
@@ -170,6 +174,15 @@ var (
 	}
 )
 
+func startPprof() {
+	go func() {
+		log.Debugf("Starting pprof server on 127.0.0.1:6060")
+		if err := http.ListenAndServe("127.0.0.1:6060", nil); err != nil {
+			log.Fatalf("pprof server failed: %v", err)
+		}
+	}()
+}
+
 func getTLSConfigurations() ([]grpc.ServerOption, *autocert.Manager, error) {
 	var (
 		err         error
diff --git a/signal/metrics/app.go b/signal/metrics/app.go
index b3457cf96..e3b1c67cd 100644
--- a/signal/metrics/app.go
+++ b/signal/metrics/app.go
@@ -20,6 +20,8 @@ type AppMetrics struct {
 	MessagesForwarded      metric.Int64Counter
 	MessageForwardFailures metric.Int64Counter
 	MessageForwardLatency  metric.Float64Histogram
+
+	MessageSize metric.Int64Histogram
 }
 
 func NewAppMetrics(meter metric.Meter) (*AppMetrics, error) {
@@ -97,6 +99,16 @@ func NewAppMetrics(meter metric.Meter) (*AppMetrics, error) {
 		return nil, err
 	}
 
+	messageSize, err := meter.Int64Histogram(
+		"message.size.bytes",
+		metric.WithUnit("bytes"),
+		metric.WithExplicitBucketBoundaries(getMessageSizeBucketBoundaries()...),
+		metric.WithDescription("Records the size of each message sent"),
+	)
+	if err != nil {
+		return nil, err
+	}
+
 	return &AppMetrics{
 		Meter: meter,
 
@@ -112,9 +124,26 @@ func NewAppMetrics(meter metric.Meter) (*AppMetrics, error) {
 		MessagesForwarded:      messagesForwarded,
 		MessageForwardFailures: messageForwardFailures,
 		MessageForwardLatency:  messageForwardLatency,
+
+		MessageSize: messageSize,
 	}, nil
 }
 
+func getMessageSizeBucketBoundaries() []float64 {
+	return []float64{
+		100,
+		250,
+		500,
+		1000,
+		5000,
+		10000,
+		50000,
+		100000,
+		500000,
+		1000000,
+	}
+}
+
 func getStandardBucketBoundaries() []float64 {
 	return []float64{
 		0.1,
diff --git a/signal/server/signal.go b/signal/server/signal.go
index abc1c367b..05cc43276 100644
--- a/signal/server/signal.go
+++ b/signal/server/signal.go
@@ -13,6 +13,7 @@ import (
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/status"
+	gproto "google.golang.org/protobuf/proto"
 
 	"github.com/netbirdio/netbird/signal/metrics"
 	"github.com/netbirdio/netbird/signal/peer"
@@ -175,4 +176,5 @@ func (s *Server) forwardMessageToPeer(ctx context.Context, msg *proto.EncryptedM
 	// in milliseconds
 	s.metrics.MessageForwardLatency.Record(ctx, float64(time.Since(start).Nanoseconds())/1e6, metric.WithAttributes(attribute.String(labelType, labelTypeStream)))
 	s.metrics.MessagesForwarded.Add(ctx, 1)
+	s.metrics.MessageSize.Record(ctx, int64(gproto.Size(msg)), metric.WithAttributes(attribute.String(labelType, labelTypeMessage)))
 }