Add sampleRatio cli flag, updating cli flag names, and other variable names

cmd/geth/main.go

@@ -196,8 +196,9 @@ var (
 		utils.RPCTxSyncDefaultTimeoutFlag,
 		utils.RPCTxSyncMaxTimeoutFlag,
 		utils.RPCGlobalRangeLimitFlag,
-		utils.RPCTracingFlag,
-		utils.RPCTracingEndpointFlag,
+		utils.RPCTelemetryFlag,
+		utils.RPCTelemetryEndpointFlag,
+		utils.RPCTelemetrySampleRatioFlag,
 	}
 
 	metricsFlags = []cli.Flag{

cmd/utils/flags.go

@@ -1043,16 +1043,23 @@ Please note that --` + MetricsHTTPFlag.Name + ` must be set to start the server.
 		Category: flags.MetricsCategory,
 	}
 
-	// RPC Tracing
-	RPCTracingFlag = &cli.BoolFlag{
-		Name:     "rpc.tracing",
-		Usage:    "Enable RPC tracing",
+	// RPC Telemetry
+	RPCTelemetryFlag = &cli.BoolFlag{
+		Name:     "rpc.telemetry",
+		Usage:    "Enable RPC telemetry",
 		Category: flags.APICategory,
 	}
 
-	RPCTracingEndpointFlag = &cli.StringFlag{
-		Name:     "rpc.tracing.endpoint",
-		Usage:    "Defines where RPC traces are sent (e.g., http://localhost:4318)",
+	RPCTelemetryEndpointFlag = &cli.StringFlag{
+		Name:     "rpc.telemetry.endpoint",
+		Usage:    "Defines where RPC telemetry is sent (e.g., http://localhost:4318)",
+		Category: flags.APICategory,
+	}
+
+	RPCTelemetrySampleRatioFlag = &cli.Float64Flag{
+		Name:     "rpc.telemetry.sample-ratio",
+		Usage:    "Defines the sampling ratio for RPC telemetry (0.0 to 1.0)",
+		Value:    1.0,
 		Category: flags.APICategory,
 	}
 )

cmd/utils/telemetry.go

@@ -1,4 +1,4 @@
-// Copyright 2025 The go-ethereum Authors
+// Copyright 2026 The go-ethereum Authors
 // This file is part of go-ethereum.
 //
 // go-ethereum is free software: you can redistribute it and/or modify
@@ -18,6 +18,7 @@ package utils
 
 import (
 	"context"
+	"fmt"
 	"time"
 
 	"github.com/ethereum/go-ethereum/internal/telemetry/config"
@@ -26,21 +27,21 @@ import (
 	"github.com/urfave/cli/v2"
 )
 
-// telemetryService wraps the telemetry Provider to implement node.Lifecycle.
+// telemetryService wraps the TelemetryProvider to implement node.Lifecycle.
 type telemetryService struct {
-	provider *config.Provider
+	telemetryProvider *config.TelemetryProvider
 }
 
 // Start implements node.Lifecycle.
 func (t *telemetryService) Start() error {
-	return nil // Provider is already started during setup
+	return nil // TelemetryProvider is already started during setup
 }
 
 // Stop implements node.Lifecycle.
 func (t *telemetryService) Stop() error {
 	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
 	defer cancel()
-	if err := t.provider.Shutdown(ctx); err != nil {
+	if err := t.telemetryProvider.Shutdown(ctx); err != nil {
 		log.Error("Failed to stop telemetry service", "err", err)
 		return err
 	}
@@ -50,13 +51,17 @@ func (t *telemetryService) Stop() error {
 
 // SetupTelemetry initializes OpenTelemetry tracing based on CLI flags.
 func SetupTelemetry(ctx *cli.Context) (*telemetryService, error) {
-	if !ctx.Bool(RPCTracingFlag.Name) {
+	if !ctx.Bool(RPCTelemetryFlag.Name) {
 		return nil, nil
 	}
-	endpoint := ctx.String(RPCTracingEndpointFlag.Name)
+	endpoint := ctx.String(RPCTelemetryEndpointFlag.Name)
 	if endpoint == "" {
 		return nil, nil
 	}
+	sampleRatio := ctx.Float64(RPCTelemetrySampleRatioFlag.Name)
+	if sampleRatio < 0 || sampleRatio > 1 {
+		return nil, fmt.Errorf("invalid sample ratio: %f", sampleRatio)
+	}
 	setupCtx := ctx.Context
 	if setupCtx == nil {
 		setupCtx = context.Background()
@@ -66,12 +71,13 @@ func SetupTelemetry(ctx *cli.Context) (*telemetryService, error) {
 	handle, err := config.Setup(
 		setupCtx,
 		endpoint,
+		sampleRatio,
 	)
 	if err != nil {
 		return nil, err
 	}
 	log.Info("Telemetry enabled", "endpoint", endpoint)
-	return &telemetryService{provider: handle}, nil
+	return &telemetryService{telemetryProvider: handle}, nil
 }
 
 // RegisterTelemetryService registers the telemetryService with the node.

internal/telemetry/config/config.go

@@ -1,4 +1,4 @@
-// Copyright 2025 The go-ethereum Authors
+// Copyright 2026 The go-ethereum Authors
 // This file is part of the go-ethereum library.
 //
 // The go-ethereum library is free software: you can redistribute it and/or modify
@@ -31,18 +31,18 @@ import (
 	semconv "go.opentelemetry.io/otel/semconv/v1.38.0"
 )
 
-// Provider wraps a TracerProvider and exposes a Shutdown method.
-type Provider struct {
+// TelemetryProvider wraps a TracerProvider and exposes the Shutdown method.
+type TelemetryProvider struct {
 	tracerProvider *sdktrace.TracerProvider
 }
 
-// Shutdown shuts down the tracer provider.
-func (p *Provider) Shutdown(ctx context.Context) error {
-	return p.tracerProvider.Shutdown(ctx)
+// Shutdown shuts down the TracerProvider.
+func (t *TelemetryProvider) Shutdown(ctx context.Context) error {
+	return t.tracerProvider.Shutdown(ctx)
 }
 
-// Setup initializes OpenTelemetry tracing with the given parameters.
-func Setup(ctx context.Context, endpoint string) (*Provider, error) {
+// Setup initializes telemetry with the given parameters.
+func Setup(ctx context.Context, endpoint string, sampleRatio float64) (*TelemetryProvider, error) {
 	// Create exporter based on endpoint URL
 	u, err := url.Parse(endpoint)
 	if err != nil {
@@ -68,6 +68,10 @@ func Setup(ctx context.Context, endpoint string) (*Provider, error) {
 		return nil, fmt.Errorf("failed to create telemetry exporter: %w", err)
 	}
 
+	// If no parent span is available, then sampleRatio of traces are sampled;
+	// otherwise, inherit the parent's sampling decision.
+	sampler := sdktrace.ParentBased(sdktrace.ParentBased(sdktrace.TraceIDRatioBased(sampleRatio)))
+
 	// Create resource with service and client information
 	res := resource.NewWithAttributes(
 		semconv.SchemaURL,
@@ -77,6 +81,7 @@ func Setup(ctx context.Context, endpoint string) (*Provider, error) {
 
 	// Create TracerProvider
 	tp := sdktrace.NewTracerProvider(
+		sdktrace.WithSampler(sampler),
 		sdktrace.WithBatcher(exporter),
 		sdktrace.WithResource(res),
 	)
@@ -91,5 +96,5 @@ func Setup(ctx context.Context, endpoint string) (*Provider, error) {
 		propagation.Baggage{},
 	))
 
-	return &Provider{tracerProvider: tp}, nil
+	return &TelemetryProvider{tracerProvider: tp}, nil
 }