fix(otel): samples-cpu conversion

Author: korniltsev

pkg/ingester/otlp/convert.go

@@ -39,6 +39,7 @@ type profileBuilder struct {
 	unsymbolziedFuncNameMap map[string]uint64
 	locationMap             map[*otelProfile.Location]uint64
 	mappingMap              map[*otelProfile.Mapping]uint64
+	cpuConversion           bool
 }
 
 func newProfileBuilder(src *otelProfile.Profile) *profileBuilder {
@@ -68,7 +69,22 @@ func newProfileBuilder(src *otelProfile.Profile) *profileBuilder {
 			Unit: res.addstr("ms"),
 		}}
 		res.dst.DefaultSampleType = res.addstr("samples")
+	} else if len(res.dst.SampleType) == 1 && res.dst.PeriodType != nil && res.dst.Period != 0 {
+		profileType := fmt.Sprintf("%s:%s:%s:%s",
+			res.dst.StringTable[res.dst.SampleType[0].Type],
+			res.dst.StringTable[res.dst.SampleType[0].Unit],
+			res.dst.StringTable[res.dst.PeriodType.Type],
+			res.dst.StringTable[res.dst.PeriodType.Unit],
+		)
+		if profileType == "samples:count:cpu:nanoseconds" {
+			res.dst.SampleType = []*googleProfile.ValueType{{
+				Type: res.addstr("cpu"),
+				Unit: res.addstr("nanoseconds"),
+			}}
+			res.cpuConversion = true
+		}
 	}
+
 	if res.dst.TimeNanos == 0 {
 		res.dst.TimeNanos = time.Now().UnixNano()
 	}
@@ -191,6 +207,8 @@ func (p *profileBuilder) convertSampleBack(os *otelProfile.Sample) *googleProfil
 
 	if len(gs.Value) == 0 {
 		gs.Value = []int64{int64(len(os.TimestampsUnixNano))}
+	} else if len(gs.Value) == 1 && p.cpuConversion {
+		gs.Value[0] *= p.src.Period
 	}
 	p.convertSampleAttributesToLabelsBack(os, gs)
 

pkg/ingester/otlp/ingest_handler_test.go

@@ -416,8 +416,8 @@ func TestDifferentServiceNames(t *testing.T) {
 
 	// Add sample types and period type
 	otlpb.profile.SampleType = []*v1experimental.ValueType{{
-		Type: otlpb.addstr("cpu"),
-		Unit: otlpb.addstr("nanoseconds"),
+		Type: otlpb.addstr("samples"),
+		Unit: otlpb.addstr("count"),
 	}}
 	otlpb.profile.PeriodType = &v1experimental.ValueType{
 		Type: otlpb.addstr("cpu"),
@@ -441,8 +441,8 @@ func TestDifferentServiceNames(t *testing.T) {
 	require.Equal(t, 2, len(profiles))
 
 	expectedStacks := map[string]string{
-		"service-a": " ||| serviceA_func2;serviceA_func1 100",
-		"service-b": " ||| serviceB_func2;serviceB_func1 200",
+		"service-a": " ||| serviceA_func2;serviceA_func1 1000000000",
+		"service-b": " ||| serviceB_func2;serviceB_func1 2000000000",
 	}
 
 	// Verify service names, stacktraces, and profile metadata in the profiles