Bytes based batching for metrics

exporter/exporterhelper/internal/sizer/metrics_sizer.go

@@ -0,0 +1,124 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package sizer // import "go.opentelemetry.io/collector/exporter/exporterhelper/internal/sizer"
+
+import (
+	"go.opentelemetry.io/collector/pdata/pmetric"
+) // MetricsCountSizer returns the nunmber of metrics entries.
+
+type MetricsSizer interface {
+	MetricsSize(md pmetric.Metrics) (count int)
+	ResourceMetricsSize(rm pmetric.ResourceMetrics) (count int)
+	ScopeMetricsSize(sm pmetric.ScopeMetrics) (count int)
+	MetricSize(m pmetric.Metric) int
+	DeltaSize(newItemSize int) int
+	NumberDataPointSize(ndp pmetric.NumberDataPoint) int
+	HistogramDataPointSize(hdp pmetric.HistogramDataPoint) int
+	ExponentialHistogramDataPointSize(ehdp pmetric.ExponentialHistogramDataPoint) int
+	SummaryDataPointSize(sdps pmetric.SummaryDataPoint) int
+}
+
+type MetricsBytesSizer struct {
+	pmetric.ProtoMarshaler
+}
+
+var _ MetricsSizer = &MetricsBytesSizer{}
+
+// DeltaSize() returns the delta size of a proto slice when a new item is added.
+// Example:
+//
+//	prevSize := proto1.Size()
+//	proto1.RepeatedField().AppendEmpty() = proto2
+//
+// Then currSize of proto1 can be calculated as
+//
+//	currSize := (prevSize + sizer.DeltaSize(proto2.Size()))
+//
+// This is derived from opentelemetry-collector/pdata/internal/data/protogen/metrics/v1/metrics.pb.go
+// which is generated with gogo/protobuf.
+func (s *MetricsBytesSizer) DeltaSize(newItemSize int) int {
+	return 1 + newItemSize + sov(uint64(newItemSize)) //nolint:gosec // disable G115
+}
+
+type MetricsCountSizer struct{}
+
+var _ MetricsSizer = &MetricsCountSizer{}
+
+func (s *MetricsCountSizer) MetricsSize(md pmetric.Metrics) int {
+	return md.DataPointCount()
+}
+
+func (s *MetricsCountSizer) ResourceMetricsSize(rm pmetric.ResourceMetrics) (count int) {
+	for i := 0; i < rm.ScopeMetrics().Len(); i++ {
+		count += s.ScopeMetricsSize(rm.ScopeMetrics().At(i))
+	}
+	return count
+}
+
+func (s *MetricsCountSizer) ScopeMetricsSize(sm pmetric.ScopeMetrics) (count int) {
+	for i := 0; i < sm.Metrics().Len(); i++ {
+		count += s.MetricSize(sm.Metrics().At(i))
+	}
+	return count
+}
+
+func (s *MetricsCountSizer) MetricSize(m pmetric.Metric) int {
+	switch m.Type() {
+	case pmetric.MetricTypeGauge:
+		return m.Gauge().DataPoints().Len()
+	case pmetric.MetricTypeSum:
+		return m.Sum().DataPoints().Len()
+	case pmetric.MetricTypeHistogram:
+		return m.Histogram().DataPoints().Len()
+	case pmetric.MetricTypeExponentialHistogram:
+		return m.ExponentialHistogram().DataPoints().Len()
+	case pmetric.MetricTypeSummary:
+		return m.Summary().DataPoints().Len()
+	}
+	return 0
+}
+
+func (s *MetricsCountSizer) DeltaSize(newItemSize int) int {
+	return newItemSize
+}
+
+func (s *MetricsCountSizer) NumberDataPointSize(_ pmetric.NumberDataPoint) int {
+	return 1
+}
+
+func (s *MetricsCountSizer) HistogramDataPointSize(_ pmetric.HistogramDataPoint) int {
+	return 1
+}
+
+func (s *MetricsCountSizer) ExponentialHistogramDataPointSize(_ pmetric.ExponentialHistogramDataPoint) int {
+	return 1
+}
+
+func (s *MetricsCountSizer) SummaryDataPointSize(_ pmetric.SummaryDataPoint) int {
+	return 1
+}
+
+// func (s *LogsCountSizer) LogsSize(ld plog.Logs) int {
+// 	return ld.LogRecordCount()
+// }
+
+// func (s *LogsCountSizer) ResourceLogsSize(rl plog.ResourceLogs) int {
+// 	count := 0
+// 	for k := 0; k < rl.ScopeLogs().Len(); k++ {
+// 		count += rl.ScopeLogs().At(k).LogRecords().Len()
+// 	}
+// 	return count
+// }
+
+// func (s *LogsCountSizer) ScopeLogsSize(sl plog.ScopeLogs) int {
+// 	return sl.LogRecords().Len()
+// }
+
+// func (s *LogsCountSizer) LogRecordSize(_ plog.LogRecord) int {
+// 	return 1
+// }
+
+// func (s *LogsCountSizer) DeltaSize(newItemSize int) int {
+// 	return newItemSize
+// }

exporter/exporterhelper/internal/sizer/metrics_sizer_test.go

@@ -0,0 +1,74 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+package sizer // import "go.opentelemetry.io/collector/exporter/exporterhelper/internal/sizer"
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"go.opentelemetry.io/collector/pdata/testdata"
+)
+
+func TestMetricsCountSizer(t *testing.T) {
+	md := testdata.GenerateMetrics(7)
+	sizer := MetricsCountSizer{}
+	require.Equal(t, 14, sizer.MetricsSize(md))
+
+	rm := md.ResourceMetrics().At(0)
+	require.Equal(t, 14, sizer.ResourceMetricsSize(rm))
+
+	sm := rm.ScopeMetrics().At(0)
+	require.Equal(t, 14, sizer.ScopeMetricsSize(sm))
+
+	// Test different metric types
+	require.Equal(t, 2, sizer.MetricSize(sm.Metrics().At(0)))
+
+	// Test data point sizes
+	require.Equal(t, 1, sizer.NumberDataPointSize(sm.Metrics().At(0).Gauge().DataPoints().At(0)))
+	require.Equal(t, 1, sizer.NumberDataPointSize(sm.Metrics().At(1).Gauge().DataPoints().At(0)))
+	require.Equal(t, 1, sizer.NumberDataPointSize(sm.Metrics().At(2).Sum().DataPoints().At(0)))
+	require.Equal(t, 1, sizer.NumberDataPointSize(sm.Metrics().At(3).Sum().DataPoints().At(0)))
+	require.Equal(t, 1, sizer.HistogramDataPointSize(sm.Metrics().At(4).Histogram().DataPoints().At(0)))
+	require.Equal(t, 1, sizer.ExponentialHistogramDataPointSize(sm.Metrics().At(5).ExponentialHistogram().DataPoints().At(0)))
+	require.Equal(t, 1, sizer.SummaryDataPointSize(sm.Metrics().At(6).Summary().DataPoints().At(0)))
+
+	prevSize := sizer.ScopeMetricsSize(sm)
+	sm.Metrics().At(0).CopyTo(sm.Metrics().AppendEmpty())
+	require.Equal(t, sizer.ScopeMetricsSize(sm), prevSize+sizer.DeltaSize(sizer.MetricSize(sm.Metrics().At(0))))
+}
+
+func TestMetricsBytesSizer(t *testing.T) {
+	md := testdata.GenerateMetrics(7)
+	sizer := MetricsBytesSizer{}
+	require.Equal(t, 1594, sizer.MetricsSize(md))
+
+	rm := md.ResourceMetrics().At(0)
+	require.Equal(t, 1591, sizer.ResourceMetricsSize(rm))
+
+	sm := rm.ScopeMetrics().At(0)
+	require.Equal(t, 1546, sizer.ScopeMetricsSize(sm))
+
+	// Test different metric types
+	require.Equal(t, 130, sizer.MetricSize(sm.Metrics().At(0)))
+
+	// Test data point sizes
+	require.Equal(t, 55, sizer.NumberDataPointSize(sm.Metrics().At(0).Gauge().DataPoints().At(0)))
+	require.Equal(t, 83, sizer.NumberDataPointSize(sm.Metrics().At(1).Gauge().DataPoints().At(0)))
+	require.Equal(t, 55, sizer.NumberDataPointSize(sm.Metrics().At(2).Sum().DataPoints().At(0)))
+	require.Equal(t, 83, sizer.NumberDataPointSize(sm.Metrics().At(3).Sum().DataPoints().At(0)))
+	require.Equal(t, 92, sizer.HistogramDataPointSize(sm.Metrics().At(4).Histogram().DataPoints().At(0)))
+	require.Equal(t, 119, sizer.ExponentialHistogramDataPointSize(sm.Metrics().At(5).ExponentialHistogram().DataPoints().At(0)))
+	require.Equal(t, 92, sizer.SummaryDataPointSize(sm.Metrics().At(6).Summary().DataPoints().At(0)))
+
+	prevSize := sizer.ScopeMetricsSize(sm)
+	sm.Metrics().At(0).CopyTo(sm.Metrics().AppendEmpty())
+	require.Equal(t, sizer.ScopeMetricsSize(sm), prevSize+sizer.DeltaSize(sizer.MetricSize(sm.Metrics().At(0))))
+}
+
+func TestMetricsBytesDeltaSize(t *testing.T) {
+	sizer := MetricsBytesSizer{}
+	require.Equal(t, 129, sizer.DeltaSize(127))
+	require.Equal(t, 131, sizer.DeltaSize(128))
+	require.Equal(t, 242, sizer.DeltaSize(239))
+}

exporter/exporterhelper/metrics.go

@@ -14,6 +14,7 @@ import (
 	"go.opentelemetry.io/collector/consumer/consumererror"
 	"go.opentelemetry.io/collector/exporter"
 	"go.opentelemetry.io/collector/exporter/exporterhelper/internal"
+	"go.opentelemetry.io/collector/exporter/exporterhelper/internal/sizer"
 	"go.opentelemetry.io/collector/pdata/pmetric"
 	"go.opentelemetry.io/collector/pipeline"
 )
@@ -24,16 +25,16 @@ var (
 )
 
 type metricsRequest struct {
-	md               pmetric.Metrics
-	pusher           consumer.ConsumeMetricsFunc
-	cachedItemsCount int
+	md         pmetric.Metrics
+	pusher     consumer.ConsumeMetricsFunc
+	cachedSize int
 }
 
 func newMetricsRequest(md pmetric.Metrics, pusher consumer.ConsumeMetricsFunc) Request {
 	return &metricsRequest{
-		md:               md,
-		pusher:           pusher,
-		cachedItemsCount: md.DataPointCount(),
+		md:         md,
+		pusher:     pusher,
+		cachedSize: -1,
 	}
 }
 
@@ -66,11 +67,18 @@ func (req *metricsRequest) Export(ctx context.Context) error {
 }
 
 func (req *metricsRequest) ItemsCount() int {
-	return req.cachedItemsCount
+	return req.md.DataPointCount()
 }
 
-func (req *metricsRequest) setCachedItemsCount(count int) {
-	req.cachedItemsCount = count
+func (req *metricsRequest) Size(sizer sizer.MetricsSizer) int {
+	if req.cachedSize == -1 {
+		req.cachedSize = sizer.MetricsSize(req.md)
+	}
+	return req.cachedSize
+}
+
+func (req *metricsRequest) setCachedSize(count int) {
+	req.cachedSize = count
 }
 
 type metricsExporter struct {