Extract Label Pair to Fingerprint indexing.

storage/metric/instrumentation.go

@@ -43,6 +43,8 @@ const (
 	hasIndexMetric              = "has_index_metric"
 	hasLabelName                = "has_label_name"
 	hasLabelPair                = "has_label_pair"
+	indexLabelNames             = "index_label_names"
+	indexLabelPairs             = "index_label_pairs"
 	indexMetric                 = "index_metric"
 	indexMetrics                = "index_metrics"
 	rebuildDiskFrontier         = "rebuild_disk_frontier"

storage/metric/leveldb.go

@@ -269,38 +269,20 @@ func (l *LevelDBMetricPersistence) findUnindexedMetrics(candidates map[model.Fin
 	return
 }
 
-// indexMetrics takes groups of samples, determines which ones contain metrics
+// indexLabelNames accumulates all label name to fingerprint index entries for
-// that are unknown to the storage stack, and then proceeds to update all
+// the dirty metrics, appends the new dirtied metrics, sorts, and bulk updates
-// affected indices.
+// the index to reflect the new state.
-func (l *LevelDBMetricPersistence) indexMetrics(fingerprints map[model.Fingerprint]model.Metric) (err error) {
+func (l *LevelDBMetricPersistence) indexLabelNames(metrics map[model.Fingerprint]model.Metric) (err error) {
 	begin := time.Now()
 	defer func() {
 		duration := time.Since(begin)
 
-		recordOutcome(duration, err, map[string]string{operation: indexMetrics, result: success}, map[string]string{operation: indexMetrics, result: failure})
+		recordOutcome(duration, err, map[string]string{operation: indexLabelNames, result: success}, map[string]string{operation: indexLabelNames, result: failure})
 	}()
 
-	var (
-		absentMetrics map[model.Fingerprint]model.Metric
-	)
-
-	absentMetrics, err = l.findUnindexedMetrics(fingerprints)
-	if err != nil {
-		panic(err)
-	}
-
-	// TODO: For the missing fingerprints, determine what label names and pairs
-	// are absent and act accordingly and append fingerprints.
-	var (
-		doneBuildingLabelNameIndex = make(chan interface{})
-		doneBuildingLabelPairIndex = make(chan interface{})
-	)
-
-	// Update LabelName -> Fingerprint index.
-	go func() {
 	labelNameFingerprints := map[model.LabelName]utility.Set{}
 
-		for fingerprint, metric := range absentMetrics {
+	for fingerprint, metric := range metrics {
 		for labelName := range metric {
 			fingerprintSet, ok := labelNameFingerprints[labelName]
 			if !ok {
@@ -309,8 +291,7 @@ func (l *LevelDBMetricPersistence) indexMetrics(fingerprints map[model.Fingerpri
 				fingerprints, err := l.GetFingerprintsForLabelName(labelName)
 				if err != nil {
 					panic(err)
-						doneBuildingLabelNameIndex <- err
+					return err
-						return
 				}
 
 				for _, fingerprint := range fingerprints {
@@ -345,21 +326,29 @@ func (l *LevelDBMetricPersistence) indexMetrics(fingerprints map[model.Fingerpri
 		batch.Put(coding.NewProtocolBufferEncoder(key), coding.NewProtocolBufferEncoder(value))
 	}
 
-		err := l.labelNameToFingerprints.Commit(batch)
+	err = l.labelNameToFingerprints.Commit(batch)
 	if err != nil {
 		panic(err)
-			doneBuildingLabelNameIndex <- err
 		return
 	}
 
-		doneBuildingLabelNameIndex <- true
+	return
+}
+
+// indexLabelPairs accumulates all label pair to fingerprint index entries for
+// the dirty metrics, appends the new dirtied metrics, sorts, and bulk updates
+// the index to reflect the new state.
+func (l *LevelDBMetricPersistence) indexLabelPairs(metrics map[model.Fingerprint]model.Metric) (err error) {
+	begin := time.Now()
+	defer func() {
+		duration := time.Since(begin)
+
+		recordOutcome(duration, err, map[string]string{operation: indexLabelPairs, result: success}, map[string]string{operation: indexLabelPairs, result: failure})
 	}()
 
-	// Update LabelPair -> Fingerprint index.
-	go func() {
 	labelPairFingerprints := map[model.LabelPair]utility.Set{}
 
-		for fingerprint, metric := range absentMetrics {
+	for fingerprint, metric := range metrics {
 		for labelName, labelValue := range metric {
 			labelPair := model.LabelPair{
 				Name:  labelName,
@@ -374,8 +363,7 @@ func (l *LevelDBMetricPersistence) indexMetrics(fingerprints map[model.Fingerpri
 				})
 				if err != nil {
 					panic(err)
-						doneBuildingLabelPairIndex <- err
+					return err
-						return
 				}
 
 				for _, fingerprint := range fingerprints {
@@ -411,27 +399,64 @@ func (l *LevelDBMetricPersistence) indexMetrics(fingerprints map[model.Fingerpri
 		batch.Put(coding.NewProtocolBufferEncoder(key), coding.NewProtocolBufferEncoder(value))
 	}
 
-		err := l.labelSetToFingerprints.Commit(batch)
+	err = l.labelSetToFingerprints.Commit(batch)
 	if err != nil {
 		panic(err)
-			doneBuildingLabelPairIndex <- true
 		return
 	}
 
-		doneBuildingLabelPairIndex <- true
+	return
+}
+
+// indexMetrics takes groups of samples, determines which ones contain metrics
+// that are unknown to the storage stack, and then proceeds to update all
+// affected indices.
+func (l *LevelDBMetricPersistence) indexMetrics(fingerprints map[model.Fingerprint]model.Metric) (err error) {
+	begin := time.Now()
+	defer func() {
+		duration := time.Since(begin)
+
+		recordOutcome(duration, err, map[string]string{operation: indexMetrics, result: success}, map[string]string{operation: indexMetrics, result: failure})
+	}()
+
+	var (
+		absentMetrics map[model.Fingerprint]model.Metric
+	)
+
+	absentMetrics, err = l.findUnindexedMetrics(fingerprints)
+	if err != nil {
+		panic(err)
+	}
+
+	if len(absentMetrics) == 0 {
+		return
+	}
+
+	// TODO: For the missing fingerprints, determine what label names and pairs
+	// are absent and act accordingly and append fingerprints.
+	var (
+		doneBuildingLabelNameIndex = make(chan error)
+		doneBuildingLabelPairIndex = make(chan error)
+	)
+
+	go func() {
+		doneBuildingLabelNameIndex <- l.indexLabelNames(absentMetrics)
+	}()
+
+	// Update LabelPair -> Fingerprint index.
+	go func() {
+		doneBuildingLabelPairIndex <- l.indexLabelPairs(absentMetrics)
 	}()
 
 	makeTopLevelIndex := true
 
-	v := <-doneBuildingLabelNameIndex
+	err = <-doneBuildingLabelNameIndex
-	_, ok := v.(error)
+	if err != nil {
-	if ok {
 		panic(err)
 		makeTopLevelIndex = false
 	}
-	v = <-doneBuildingLabelPairIndex
+	err = <-doneBuildingLabelPairIndex
-	_, ok = v.(error)
+	if err != nil {
-	if ok {
 		panic(err)
 		makeTopLevelIndex = false
 	}