Add processor duration metric (#13227)

#### Description

Add duration metric to processors.

#### Testing

Unit tests added.

#### Documentation

Implements issue [Processor duration metric
#13231](https://github.com/open-telemetry/opentelemetry-collector/issues/13231).

Basic documentation generated by mdatagen.

---------

Co-authored-by: Joshua MacDonald <jmacd@users.noreply.github.com>
Co-authored-by: Pablo Baeyens <pablo.baeyens@datadoghq.com>

.chloggen/processor-internal-duration.yaml

@@ -0,0 +1,25 @@
+# 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. otlpreceiver)
+component: processorhelper
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Add processor internal duration metric.
+
+# One or more tracking issues or pull requests related to the change
+issues: [13231]
+
+# (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:
+
+# 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: [user]

processor/processorhelper/documentation.md

@@ -14,6 +14,14 @@ Number of items passed to the processor. [alpha]
 | ---- | ----------- | ---------- | --------- |
 | {items} | Sum | Int | true |
 
+### otelcol_processor_internal_duration
+
+Duration of time taken to process a batch of telemetry data through the processor. [alpha]
+
+| Unit | Metric Type | Value Type |
+| ---- | ----------- | ---------- |
+| s | Histogram | Double |
+
 ### otelcol_processor_outgoing_items
 
 Number of items emitted from the processor. [alpha]

processor/processorhelper/internal/metadata/generated_telemetry.go

@@ -27,6 +27,7 @@ type TelemetryBuilder struct {
 	mu                        sync.Mutex
 	registrations             []metric.Registration
 	ProcessorIncomingItems    metric.Int64Counter
+	ProcessorInternalDuration metric.Float64Histogram
 	ProcessorOutgoingItems    metric.Int64Counter
 }
 
@@ -65,6 +66,12 @@ func NewTelemetryBuilder(settings component.TelemetrySettings, options ...Teleme
 		metric.WithUnit("{items}"),
 	)
 	errs = errors.Join(errs, err)
+	builder.ProcessorInternalDuration, err = builder.meter.Float64Histogram(
+		"otelcol_processor_internal_duration",
+		metric.WithDescription("Duration of time taken to process a batch of telemetry data through the processor. [alpha]"),
+		metric.WithUnit("s"),
+	)
+	errs = errors.Join(errs, err)
 	builder.ProcessorOutgoingItems, err = builder.meter.Int64Counter(
 		"otelcol_processor_outgoing_items",
 		metric.WithDescription("Number of items emitted from the processor. [alpha]"),

processor/processorhelper/internal/metadatatest/generated_telemetrytest.go

@@ -28,6 +28,21 @@ func AssertEqualProcessorIncomingItems(t *testing.T, tt *componenttest.Telemetry
 	metricdatatest.AssertEqual(t, want, got, opts...)
 }
 
+func AssertEqualProcessorInternalDuration(t *testing.T, tt *componenttest.Telemetry, dps []metricdata.HistogramDataPoint[float64], opts ...metricdatatest.Option) {
+	want := metricdata.Metrics{
+		Name:        "otelcol_processor_internal_duration",
+		Description: "Duration of time taken to process a batch of telemetry data through the processor. [alpha]",
+		Unit:        "s",
+		Data: metricdata.Histogram[float64]{
+			Temporality: metricdata.CumulativeTemporality,
+			DataPoints:  dps,
+		},
+	}
+	got, err := tt.GetMetric("otelcol_processor_internal_duration")
+	require.NoError(t, err)
+	metricdatatest.AssertEqual(t, want, got, opts...)
+}
+
 func AssertEqualProcessorOutgoingItems(t *testing.T, tt *componenttest.Telemetry, dps []metricdata.DataPoint[int64], opts ...metricdatatest.Option) {
 	want := metricdata.Metrics{
 		Name:        "otelcol_processor_outgoing_items",

processor/processorhelper/internal/metadatatest/generated_telemetrytest_test.go

@@ -20,10 +20,14 @@ func TestSetupTelemetry(t *testing.T) {
 	require.NoError(t, err)
 	defer tb.Shutdown()
 	tb.ProcessorIncomingItems.Add(context.Background(), 1)
+	tb.ProcessorInternalDuration.Record(context.Background(), 1)
 	tb.ProcessorOutgoingItems.Add(context.Background(), 1)
 	AssertEqualProcessorIncomingItems(t, testTel,
 		[]metricdata.DataPoint[int64]{{Value: 1}},
 		metricdatatest.IgnoreTimestamp())
+	AssertEqualProcessorInternalDuration(t, testTel,
+		[]metricdata.HistogramDataPoint[float64]{{}}, metricdatatest.IgnoreValue(),
+		metricdatatest.IgnoreTimestamp())
 	AssertEqualProcessorOutgoingItems(t, testTel,
 		[]metricdata.DataPoint[int64]{{Value: 1}},
 		metricdatatest.IgnoreTimestamp())

processor/processorhelper/logs.go

@@ -6,6 +6,7 @@ package processorhelper // import "go.opentelemetry.io/collector/processor/proce
 import (
 	"context"
 	"errors"
+	"time"
 
 	"go.opentelemetry.io/otel/trace"
 
@@ -49,10 +50,14 @@ func NewLogs(
 	logsConsumer, err := consumer.NewLogs(func(ctx context.Context, ld plog.Logs) error {
 		span := trace.SpanFromContext(ctx)
 		span.AddEvent("Start processing.", eventOptions)
+
+		startTime := time.Now()
+
 		recordsIn := ld.LogRecordCount()
 
 		var errFunc error
 		ld, errFunc = logsFunc(ctx, ld)
+		obs.recordInternalDuration(ctx, startTime)
 		span.AddEvent("End processing.", eventOptions)
 		if errFunc != nil {
 			obs.recordInOut(ctx, recordsIn, 0)

processor/processorhelper/logs_test.go

@@ -183,6 +183,33 @@ func TestLogs_RecordIn_ErrorOut(t *testing.T) {
 		}, metricdatatest.IgnoreTimestamp())
 }
 
+func TestLogs_ProcessInternalDuration(t *testing.T) {
+	mockAggregate := func(_ context.Context, _ plog.Logs) (plog.Logs, error) {
+		ld := plog.NewLogs()
+		ld.ResourceLogs().AppendEmpty().ScopeLogs().AppendEmpty().LogRecords().AppendEmpty()
+		return ld, nil
+	}
+
+	incomingLogs := plog.NewLogs()
+
+	tel := componenttest.NewTelemetry()
+	lp, err := NewLogs(context.Background(), newSettings(tel), &testLogsCfg, consumertest.NewNop(), mockAggregate)
+	require.NoError(t, err)
+
+	assert.NoError(t, lp.Start(context.Background(), componenttest.NewNopHost()))
+	assert.NoError(t, lp.ConsumeLogs(context.Background(), incomingLogs))
+	assert.NoError(t, lp.Shutdown(context.Background()))
+
+	metadatatest.AssertEqualProcessorInternalDuration(t, tel,
+		[]metricdata.HistogramDataPoint[float64]{
+			{
+				Count:        1,
+				BucketCounts: []uint64{1},
+				Attributes:   attribute.NewSet(attribute.String("processor", "processorhelper"), attribute.String("otel.signal", "logs")),
+			},
+		}, metricdatatest.IgnoreTimestamp(), metricdatatest.IgnoreValue())
+}
+
 func newSettings(tel *componenttest.Telemetry) processor.Settings {
 	set := processortest.NewNopSettings(component.MustNewType("processorhelper"))
 	set.TelemetrySettings = tel.NewTelemetrySettings()

processor/processorhelper/metadata.yaml

@@ -28,3 +28,13 @@ telemetry:
       sum:
         value_type: int
         monotonic: true
+
+    processor_internal_duration:
+      enabled: true
+      stability:
+        level: alpha
+      description: Duration of time taken to process a batch of telemetry data through the processor.
+      unit: s
+      histogram:
+        async: false
+        value_type: double

processor/processorhelper/metrics.go

@@ -6,6 +6,7 @@ package processorhelper // import "go.opentelemetry.io/collector/processor/proce
 import (
 	"context"
 	"errors"
+	"time"
 
 	"go.opentelemetry.io/otel/trace"
 
@@ -49,10 +50,14 @@ func NewMetrics(
 	metricsConsumer, err := consumer.NewMetrics(func(ctx context.Context, md pmetric.Metrics) error {
 		span := trace.SpanFromContext(ctx)
 		span.AddEvent("Start processing.", eventOptions)
+
+		startTime := time.Now()
+
 		pointsIn := md.DataPointCount()
 
 		var errFunc error
 		md, errFunc = metricsFunc(ctx, md)
+		obs.recordInternalDuration(ctx, startTime)
 		span.AddEvent("End processing.", eventOptions)
 		if errFunc != nil {
 			obs.recordInOut(ctx, pointsIn, 0)

processor/processorhelper/metrics_test.go

@@ -180,3 +180,32 @@ func TestMetrics_RecordIn_ErrorOut(t *testing.T) {
 			},
 		}, metricdatatest.IgnoreTimestamp())
 }
+
+func TestMetrics_ProcessInternalDuration(t *testing.T) {
+	mockAggregate := func(_ context.Context, _ pmetric.Metrics) (pmetric.Metrics, error) {
+		md := pmetric.NewMetrics()
+		md.ResourceMetrics().AppendEmpty().ScopeMetrics().AppendEmpty().Metrics().AppendEmpty().SetEmptySum().DataPoints().AppendEmpty()
+		md.ResourceMetrics().AppendEmpty().ScopeMetrics().AppendEmpty().Metrics().AppendEmpty().SetEmptySum().DataPoints().AppendEmpty()
+		md.ResourceMetrics().AppendEmpty().ScopeMetrics().AppendEmpty().Metrics().AppendEmpty().SetEmptySum().DataPoints().AppendEmpty()
+		return md, nil
+	}
+
+	incomingMetrics := pmetric.NewMetrics()
+
+	tel := componenttest.NewTelemetry()
+	mp, err := NewMetrics(context.Background(), newSettings(tel), &testMetricsCfg, consumertest.NewNop(), mockAggregate)
+	require.NoError(t, err)
+
+	assert.NoError(t, mp.Start(context.Background(), componenttest.NewNopHost()))
+	assert.NoError(t, mp.ConsumeMetrics(context.Background(), incomingMetrics))
+	assert.NoError(t, mp.Shutdown(context.Background()))
+
+	metadatatest.AssertEqualProcessorInternalDuration(t, tel,
+		[]metricdata.HistogramDataPoint[float64]{
+			{
+				Count:        1,
+				BucketCounts: []uint64{1},
+				Attributes:   attribute.NewSet(attribute.String("processor", "processorhelper"), attribute.String("otel.signal", "metrics")),
+			},
+		}, metricdatatest.IgnoreTimestamp(), metricdatatest.IgnoreValue())
+}

processor/processorhelper/obsreport.go

@@ -5,6 +5,7 @@ package processorhelper // import "go.opentelemetry.io/collector/processor/proce
 
 import (
 	"context"
+	"time"
 
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/metric"
@@ -40,3 +41,8 @@ func (or *obsReport) recordInOut(ctx context.Context, incoming, outgoing int) {
 	or.telemetryBuilder.ProcessorIncomingItems.Add(ctx, int64(incoming), or.otelAttrs)
 	or.telemetryBuilder.ProcessorOutgoingItems.Add(ctx, int64(outgoing), or.otelAttrs)
 }
+
+func (or *obsReport) recordInternalDuration(ctx context.Context, startTime time.Time) {
+	duration := time.Since(startTime)
+	or.telemetryBuilder.ProcessorInternalDuration.Record(ctx, duration.Seconds(), or.otelAttrs)
+}

processor/processorhelper/traces.go

@@ -6,6 +6,7 @@ package processorhelper // import "go.opentelemetry.io/collector/processor/proce
 import (
 	"context"
 	"errors"
+	"time"
 
 	"go.opentelemetry.io/otel/trace"
 
@@ -49,10 +50,14 @@ func NewTraces(
 	traceConsumer, err := consumer.NewTraces(func(ctx context.Context, td ptrace.Traces) error {
 		span := trace.SpanFromContext(ctx)
 		span.AddEvent("Start processing.", eventOptions)
+
+		startTime := time.Now()
+
 		spansIn := td.SpanCount()
 
 		var errFunc error
 		td, errFunc = tracesFunc(ctx, td)
+		obs.recordInternalDuration(ctx, startTime)
 		span.AddEvent("End processing.", eventOptions)
 		if errFunc != nil {
 			obs.recordInOut(ctx, spansIn, 0)

processor/processorhelper/traces_test.go

@@ -184,3 +184,30 @@ func TestTraces_RecordIn_ErrorOut(t *testing.T) {
 			},
 		}, metricdatatest.IgnoreTimestamp())
 }
+
+func TestTraces_ProcessInternalDuration(t *testing.T) {
+	mockAggregate := func(_ context.Context, _ ptrace.Traces) (ptrace.Traces, error) {
+		td := ptrace.NewTraces()
+		td.ResourceSpans().AppendEmpty().ScopeSpans().AppendEmpty().Spans().AppendEmpty()
+		return td, nil
+	}
+
+	incomingTraces := ptrace.NewTraces()
+
+	tel := componenttest.NewTelemetry()
+	tp, err := NewTraces(context.Background(), newSettings(tel), &testLogsCfg, consumertest.NewNop(), mockAggregate)
+	require.NoError(t, err)
+
+	assert.NoError(t, tp.Start(context.Background(), componenttest.NewNopHost()))
+	assert.NoError(t, tp.ConsumeTraces(context.Background(), incomingTraces))
+	assert.NoError(t, tp.Shutdown(context.Background()))
+
+	metadatatest.AssertEqualProcessorInternalDuration(t, tel,
+		[]metricdata.HistogramDataPoint[float64]{
+			{
+				Count:        1,
+				BucketCounts: []uint64{1},
+				Attributes:   attribute.NewSet(attribute.String("processor", "processorhelper"), attribute.String("otel.signal", "traces")),
+			},
+		}, metricdatatest.IgnoreTimestamp(), metricdatatest.IgnoreValue())
+}

service/service.go

@@ -379,6 +379,11 @@ func configureViews(level configtelemetry.Level) []config.View {
 			dropViewOption(&config.ViewSelector{
 				MeterName: ptr("go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"),
 			}),
+			// Drop duration metric if the level is not detailed
+			dropViewOption(&config.ViewSelector{
+				MeterName:      ptr("go.opentelemetry.io/collector/processor/processorhelper"),
+				InstrumentName: ptr("otelcol_processor_internal_duration"),
+			}),
 		)
 	}