[feat][exporter/loadbalancingexporter] add benchmarks for metrics and…

… traces consume (open-telemetry#30915)

**Description:** 
According to
open-telemetry#30141 (review)
PR adds benchmarks for functions:
- `mergeTraces`
- `mergeMetrics`
- `consumeTraces`
- `consumeMetrics`

.chloggen/mat-rumian-add-lbe-benchmarks.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: loadbalancingexporter
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: "Add benchmarks for Metrics and Traces"
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [30915]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

exporter/loadbalancingexporter/helpers_test.go

@@ -119,3 +119,57 @@ func TestMergeMetrics(t *testing.T) {
 
 	require.Equal(t, expectedMetrics, mergedMetrics)
 }
+
+func benchMergeTraces(b *testing.B, tracesCount int) {
+	traces1 := ptrace.NewTraces()
+	traces2 := ptrace.NewTraces()
+
+	for i := 0; i < tracesCount; i++ {
+		appendSimpleTraceWithID(traces2.ResourceSpans().AppendEmpty(), [16]byte{1, 2, 3, 4})
+	}
+
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		mergeTraces(traces1, traces2)
+	}
+}
+
+func BenchmarkMergeTraces_X100(b *testing.B) {
+	benchMergeTraces(b, 100)
+}
+
+func BenchmarkMergeTraces_X500(b *testing.B) {
+	benchMergeTraces(b, 500)
+}
+
+func BenchmarkMergeTraces_X1000(b *testing.B) {
+	benchMergeTraces(b, 1000)
+}
+
+func benchMergeMetrics(b *testing.B, metricsCount int) {
+	metrics1 := pmetric.NewMetrics()
+	metrics2 := pmetric.NewMetrics()
+
+	for i := 0; i < metricsCount; i++ {
+		appendSimpleMetricWithID(metrics2.ResourceMetrics().AppendEmpty(), "metrics-2")
+	}
+
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		mergeMetrics(metrics1, metrics2)
+	}
+}
+
+func BenchmarkMergeMetrics_X100(b *testing.B) {
+	benchMergeMetrics(b, 100)
+}
+
+func BenchmarkMergeMetrics_X500(b *testing.B) {
+	benchMergeMetrics(b, 500)
+}
+
+func BenchmarkMergeMetrics_X1000(b *testing.B) {
+	benchMergeMetrics(b, 1000)
+}

exporter/loadbalancingexporter/metrics_exporter_test.go

@@ -678,6 +678,97 @@ func TestRollingUpdatesWhenConsumeMetrics(t *testing.T) {
 	require.Greater(t, counter2.Load(), int64(0))
 }
 
+func appendSimpleMetricWithServiceName(metric pmetric.Metrics, serviceName string, sigName string) {
+	metric.ResourceMetrics().EnsureCapacity(1)
+	rmetrics := metric.ResourceMetrics().AppendEmpty()
+	rmetrics.Resource().Attributes().PutStr(conventions.AttributeServiceName, serviceName)
+	rmetrics.ScopeMetrics().AppendEmpty().Metrics().AppendEmpty().SetName(sigName)
+}
+
+func benchConsumeMetrics(b *testing.B, endpointsCount int, metricsCount int) {
+	sink := new(consumertest.MetricsSink)
+	componentFactory := func(ctx context.Context, endpoint string) (component.Component, error) {
+		return newMockMetricsExporter(sink.ConsumeMetrics), nil
+	}
+
+	endpoints := []string{}
+	for i := 0; i < endpointsCount; i++ {
+		endpoints = append(endpoints, fmt.Sprintf("endpoint-%d", i))
+	}
+
+	config := &Config{
+		Resolver: ResolverSettings{
+			Static: &StaticResolver{Hostnames: endpoints},
+		},
+	}
+
+	lb, err := newLoadBalancer(exportertest.NewNopCreateSettings(), config, componentFactory)
+	require.NotNil(b, lb)
+	require.NoError(b, err)
+
+	p, err := newMetricsExporter(exportertest.NewNopCreateSettings(), config)
+	require.NotNil(b, p)
+	require.NoError(b, err)
+
+	p.loadBalancer = lb
+
+	err = p.Start(context.Background(), componenttest.NewNopHost())
+	require.NoError(b, err)
+
+	metric1 := pmetric.NewMetrics()
+	metric2 := pmetric.NewMetrics()
+	for i := 0; i < endpointsCount; i++ {
+		for j := 0; j < metricsCount/endpointsCount; j++ {
+			appendSimpleMetricWithServiceName(metric2, fmt.Sprintf("service-%d", i), fmt.Sprintf("sig-%d", i))
+		}
+	}
+	simpleMetricsWithServiceName()
+	md := mergeMetrics(metric1, metric2)
+
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		err = p.ConsumeMetrics(context.Background(), md)
+		require.NoError(b, err)
+	}
+
+	b.StopTimer()
+	err = p.Shutdown(context.Background())
+	require.NoError(b, err)
+}
+
+func BenchmarkConsumeMetrics_1E100T(b *testing.B) {
+	benchConsumeMetrics(b, 1, 100)
+}
+
+func BenchmarkConsumeMetrics_1E1000T(b *testing.B) {
+	benchConsumeMetrics(b, 1, 1000)
+}
+
+func BenchmarkConsumeMetrics_5E100T(b *testing.B) {
+	benchConsumeMetrics(b, 5, 100)
+}
+
+func BenchmarkConsumeMetrics_5E500T(b *testing.B) {
+	benchConsumeMetrics(b, 5, 500)
+}
+
+func BenchmarkConsumeMetrics_5E1000T(b *testing.B) {
+	benchConsumeMetrics(b, 5, 1000)
+}
+
+func BenchmarkConsumeMetrics_10E100T(b *testing.B) {
+	benchConsumeMetrics(b, 10, 100)
+}
+
+func BenchmarkConsumeMetrics_10E500T(b *testing.B) {
+	benchConsumeMetrics(b, 10, 500)
+}
+
+func BenchmarkConsumeMetrics_10E1000T(b *testing.B) {
+	benchConsumeMetrics(b, 10, 1000)
+}
+
 func endpoint2Config() *Config {
 	return &Config{
 		Resolver: ResolverSettings{

exporter/loadbalancingexporter/trace_exporter_test.go

@@ -534,6 +534,89 @@ func TestRollingUpdatesWhenConsumeTraces(t *testing.T) {
 	require.Greater(t, counter2.Load(), int64(0))
 }
 
+func benchConsumeTraces(b *testing.B, endpointsCount int, tracesCount int) {
+	sink := new(consumertest.TracesSink)
+	componentFactory := func(ctx context.Context, endpoint string) (component.Component, error) {
+		return newMockTracesExporter(sink.ConsumeTraces), nil
+	}
+
+	endpoints := []string{}
+	for i := 0; i < endpointsCount; i++ {
+		endpoints = append(endpoints, fmt.Sprintf("endpoint-%d", i))
+	}
+
+	config := &Config{
+		Resolver: ResolverSettings{
+			Static: &StaticResolver{Hostnames: endpoints},
+		},
+	}
+
+	lb, err := newLoadBalancer(exportertest.NewNopCreateSettings(), config, componentFactory)
+	require.NotNil(b, lb)
+	require.NoError(b, err)
+
+	p, err := newTracesExporter(exportertest.NewNopCreateSettings(), config)
+	require.NotNil(b, p)
+	require.NoError(b, err)
+
+	p.loadBalancer = lb
+
+	err = p.Start(context.Background(), componenttest.NewNopHost())
+	require.NoError(b, err)
+
+	trace1 := ptrace.NewTraces()
+	trace2 := ptrace.NewTraces()
+	for i := 0; i < endpointsCount; i++ {
+		for j := 0; j < tracesCount/endpointsCount; j++ {
+			appendSimpleTraceWithID(trace2.ResourceSpans().AppendEmpty(), [16]byte{1, 2, 6, byte(i)})
+		}
+	}
+	td := mergeTraces(trace1, trace2)
+
+	b.ResetTimer()
+
+	for i := 0; i < b.N; i++ {
+		err = p.ConsumeTraces(context.Background(), td)
+		require.NoError(b, err)
+	}
+
+	b.StopTimer()
+	err = p.Shutdown(context.Background())
+	require.NoError(b, err)
+}
+
+func BenchmarkConsumeTraces_1E100T(b *testing.B) {
+	benchConsumeTraces(b, 1, 100)
+}
+
+func BenchmarkConsumeTraces_1E1000T(b *testing.B) {
+	benchConsumeTraces(b, 1, 1000)
+}
+
+func BenchmarkConsumeTraces_5E100T(b *testing.B) {
+	benchConsumeTraces(b, 5, 100)
+}
+
+func BenchmarkConsumeTraces_5E500T(b *testing.B) {
+	benchConsumeTraces(b, 5, 500)
+}
+
+func BenchmarkConsumeTraces_5E1000T(b *testing.B) {
+	benchConsumeTraces(b, 5, 1000)
+}
+
+func BenchmarkConsumeTraces_10E100T(b *testing.B) {
+	benchConsumeTraces(b, 10, 100)
+}
+
+func BenchmarkConsumeTraces_10E500T(b *testing.B) {
+	benchConsumeTraces(b, 10, 500)
+}
+
+func BenchmarkConsumeTraces_10E1000T(b *testing.B) {
+	benchConsumeTraces(b, 10, 1000)
+}
+
 func randomTraces() ptrace.Traces {
 	v1 := uint8(rand.Intn(256))
 	v2 := uint8(rand.Intn(256))