Adopt cc-lib hierarchical JobData/Statistics structs

cc-lib changed JobData, ScopedJobStats and Job.Statistics from flat maps
to structs (a .Metrics map plus array-valued Groups) to represent
filesystem (and future interconnect) metric groups. Migrate all
construction, indexing and iteration to the new API across the archive
backends, metricstore query path, metric dispatcher, archiver, importer,
tagger, taskmanager, repository and API layers.

Semantics: DecodeJobStats now projects JobData.Groups into
ScopedJobStats.Groups, and the archiver derives per-filesystem node-scope
statistics into Job.Statistics.Groups. deepCopy, resampling and the
metric/scope filter are group-aware. The metricstore internal storage
(buffers, selector tree, checkpoint/parquet) is unchanged; all conversion
stays at the LoadData/archive-codec seam.

Note: requires the corresponding cc-lib release; bump the cc-lib
dependency version once tagged (a local go.mod replace was used during
development and is intentionally not committed).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

pkg/archive/archive.go

@@ -299,7 +299,7 @@ func LoadAveragesFromArchive(
 	}
 
 	for i, m := range metrics {
-		if stat, ok := metaFile.Statistics[m]; ok {
+		if stat, ok := metaFile.Statistics.Metrics[m]; ok {
 			data[i] = append(data[i], schema.Float(stat.Avg))
 		} else {
 			data[i] = append(data[i], schema.NaN)
@@ -323,7 +323,7 @@ func LoadStatsFromArchive(
 	}
 
 	for _, m := range metrics {
-		stat, ok := metaFile.Statistics[m]
+		stat, ok := metaFile.Statistics.Metrics[m]
 		if !ok {
 			data[m] = schema.MetricStatistics{Min: 0.0, Avg: 0.0, Max: 0.0}
 			continue
@@ -349,19 +349,19 @@ func LoadScopedStatsFromArchive(
 	data, err := ar.LoadJobStats(job)
 	if err != nil {
 		cclog.Errorf("Error while loading job stats from archiveBackend: %s", err.Error())
-		return nil, err
+		return schema.ScopedJobStats{}, err
 	}
 
 	return data, nil
 }
 
 // GetStatistics returns all metric statistics for a job.
-// Returns a map of metric names to their job-level statistics.
-func GetStatistics(job *schema.Job) (map[string]schema.JobStatistics, error) {
+// Returns the job-level statistics set.
+func GetStatistics(job *schema.Job) (schema.JobStatisticsSet, error) {
 	metaFile, err := ar.LoadJobMeta(job)
 	if err != nil {
 		cclog.Errorf("Error while loading job metadata from archiveBackend: %s", err.Error())
-		return nil, err
+		return schema.JobStatisticsSet{}, err
 	}
 
 	return metaFile.Statistics, nil

pkg/archive/fsBackend.go

@@ -93,7 +93,7 @@ func loadJobData(filename string, isCompressed bool) (schema.JobData, error) {
 	f, err := os.Open(filename)
 	if err != nil {
 		cclog.Errorf("fsBackend LoadJobData()- %v", err)
-		return nil, err
+		return schema.JobData{}, err
 	}
 	defer f.Close()
 
@@ -101,7 +101,7 @@ func loadJobData(filename string, isCompressed bool) (schema.JobData, error) {
 		r, err := gzip.NewReader(f)
 		if err != nil {
 			cclog.Errorf(" %v", err)
-			return nil, err
+			return schema.JobData{}, err
 		}
 		defer r.Close()
 
@@ -126,7 +126,7 @@ func loadJobStats(filename string, isCompressed bool) (schema.ScopedJobStats, er
 	f, err := os.Open(filename)
 	if err != nil {
 		cclog.Errorf("fsBackend LoadJobStats()- %v", err)
-		return nil, err
+		return schema.ScopedJobStats{}, err
 	}
 	defer f.Close()
 
@@ -134,13 +134,13 @@ func loadJobStats(filename string, isCompressed bool) (schema.ScopedJobStats, er
 		r, err := gzip.NewReader(f)
 		if err != nil {
 			cclog.Errorf(" %v", err)
-			return nil, err
+			return schema.ScopedJobStats{}, err
 		}
 		defer r.Close()
 
 		if config.Keys.Validate {
 			if err := schema.Validate(schema.Data, r); err != nil {
-				return nil, fmt.Errorf("validate job data: %v", err)
+				return schema.ScopedJobStats{}, fmt.Errorf("validate job data: %v", err)
 			}
 		}
 
@@ -148,7 +148,7 @@ func loadJobStats(filename string, isCompressed bool) (schema.ScopedJobStats, er
 	} else {
 		if config.Keys.Validate {
 			if err := schema.Validate(schema.Data, bufio.NewReader(f)); err != nil {
-				return nil, fmt.Errorf("validate job data: %v", err)
+				return schema.ScopedJobStats{}, fmt.Errorf("validate job data: %v", err)
 			}
 		}
 		return DecodeJobStats(bufio.NewReader(f), filename)

pkg/archive/fsBackend_test.go

@@ -129,7 +129,7 @@ func TestLoadJobData(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	for _, scopes := range data {
+	for _, scopes := range data.Metrics {
 		// fmt.Printf("Metric name: %s\n", name)
 
 		if _, exists := scopes[schema.MetricScopeNode]; !exists {

pkg/archive/json.go

@@ -27,47 +27,73 @@ func DecodeJobData(r io.Reader, k string) (schema.JobData, error) {
 
 	if err, ok := data.(error); ok {
 		cclog.Warn("Error in decoded job data set")
-		return nil, err
+		return schema.JobData{}, err
 	}
 
 	return data.(schema.JobData), nil
 }
 
-func DecodeJobStats(r io.Reader, k string) (schema.ScopedJobStats, error) {
-	jobData, err := DecodeJobData(r, k)
-	// Convert schema.JobData to schema.ScopedJobStats
-	if jobData != nil {
-		scopedJobStats := make(schema.ScopedJobStats)
-		for metric, metricData := range jobData {
-			if _, ok := scopedJobStats[metric]; !ok {
-				scopedJobStats[metric] = make(map[schema.MetricScope][]*schema.ScopedStats)
+// scopedStatsFromMetrics converts a flat metric->scope->JobMetric map into the
+// corresponding metric->scope->[]*ScopedStats map. It preserves the "remove
+// empty" cleanup behaviour: a scope with no series is dropped, and a metric
+// with no remaining scopes is dropped.
+func scopedStatsFromMetrics(metrics map[string]schema.ScopedMetrics) map[string]schema.ScopedMetricStats {
+	result := make(map[string]schema.ScopedMetricStats)
+	for metric, metricData := range metrics {
+		if _, ok := result[metric]; !ok {
+			result[metric] = make(schema.ScopedMetricStats)
+		}
+
+		for scope, jobMetric := range metricData {
+			if _, ok := result[metric][scope]; !ok {
+				result[metric][scope] = make([]*schema.ScopedStats, 0)
 			}
 
-			for scope, jobMetric := range metricData {
-				if _, ok := scopedJobStats[metric][scope]; !ok {
-					scopedJobStats[metric][scope] = make([]*schema.ScopedStats, 0)
-				}
+			for _, series := range jobMetric.Series {
+				result[metric][scope] = append(result[metric][scope], &schema.ScopedStats{
+					Hostname: series.Hostname,
+					ID:       series.ID,
+					Data:     &series.Statistics,
+				})
+			}
 
-				for _, series := range jobMetric.Series {
-					scopedJobStats[metric][scope] = append(scopedJobStats[metric][scope], &schema.ScopedStats{
-						Hostname: series.Hostname,
-						ID:       series.ID,
-						Data:     &series.Statistics,
-					})
-				}
-
-				// So that one can later check len(scopedJobStats[metric][scope]): Remove from map if empty
-				if len(scopedJobStats[metric][scope]) == 0 {
-					delete(scopedJobStats[metric], scope)
-					if len(scopedJobStats[metric]) == 0 {
-						delete(scopedJobStats, metric)
-					}
+			// So that one can later check len(result[metric][scope]): Remove from map if empty
+			if len(result[metric][scope]) == 0 {
+				delete(result[metric], scope)
+				if len(result[metric]) == 0 {
+					delete(result, metric)
 				}
 			}
 		}
-		return scopedJobStats, nil
 	}
-	return nil, err
+	return result
+}
+
+func DecodeJobStats(r io.Reader, k string) (schema.ScopedJobStats, error) {
+	jobData, err := DecodeJobData(r, k)
+	if err != nil {
+		return schema.ScopedJobStats{}, err
+	}
+
+	// Convert schema.JobData to schema.ScopedJobStats
+	scopedJobStats := schema.ScopedJobStats{
+		Metrics: scopedStatsFromMetrics(jobData.Metrics),
+	}
+
+	// Project array-valued metric groups (e.g. filesystems) analogously.
+	for _, group := range jobData.Groups {
+		scopedGroup := schema.ScopedStatsGroup{Key: group.Key}
+		for _, inst := range group.Instances {
+			scopedGroup.Instances = append(scopedGroup.Instances, schema.ScopedStatsGroupInstance{
+				Name:    inst.Name,
+				Type:    inst.Type,
+				Metrics: scopedStatsFromMetrics(inst.Metrics),
+			})
+		}
+		scopedJobStats.Groups = append(scopedJobStats.Groups, scopedGroup)
+	}
+
+	return scopedJobStats, nil
 }
 
 func DecodeJobMeta(r io.Reader) (*schema.Job, error) {

pkg/archive/parquet/convert.go

@@ -23,7 +23,7 @@ func JobToParquetRow(meta *schema.Job, data *schema.JobData) (*ParquetJobRow, er
 	}
 
 	var statisticsJSON []byte
-	if meta.Statistics != nil {
+	if meta.Statistics.Metrics != nil {
 		statisticsJSON, err = json.Marshal(meta.Statistics)
 		if err != nil {
 			return nil, fmt.Errorf("marshal statistics: %w", err)

pkg/archive/parquet/convert_test.go

@@ -32,9 +32,9 @@ func TestParquetRowToJob(t *testing.T) {
 			{Hostname: "node001", HWThreads: []int{0, 1, 2, 3}},
 			{Hostname: "node002", HWThreads: []int{4, 5, 6, 7}},
 		},
-		Statistics: map[string]schema.JobStatistics{
+		Statistics: schema.JobStatisticsSet{Metrics: map[string]schema.JobStatistics{
 			"cpu_load": {Avg: 50.0, Min: 10.0, Max: 90.0},
-		},
+		}},
 		Tags: []*schema.Tag{
 			{Type: "test", Name: "tag1"},
 		},
@@ -49,7 +49,7 @@ func TestParquetRowToJob(t *testing.T) {
 		},
 	}
 
-	data := &schema.JobData{
+	data := &schema.JobData{Metrics: map[string]schema.ScopedMetrics{
 		"cpu_load": {
 			schema.MetricScopeNode: &schema.JobMetric{
 				Unit:     schema.Unit{Base: ""},
@@ -62,7 +62,7 @@ func TestParquetRowToJob(t *testing.T) {
 				},
 			},
 		},
-	}
+	}}
 
 	// Convert to parquet row
 	row, err := JobToParquetRow(meta, data)
@@ -134,10 +134,10 @@ func TestParquetRowToJob(t *testing.T) {
 		t.Errorf("Resources[0].HWThreads len = %d, want 4", len(gotMeta.Resources[0].HWThreads))
 	}
 
-	if len(gotMeta.Statistics) != 1 {
-		t.Fatalf("Statistics len = %d, want 1", len(gotMeta.Statistics))
+	if len(gotMeta.Statistics.Metrics) != 1 {
+		t.Fatalf("Statistics len = %d, want 1", len(gotMeta.Statistics.Metrics))
 	}
-	if stat, ok := gotMeta.Statistics["cpu_load"]; !ok {
+	if stat, ok := gotMeta.Statistics.Metrics["cpu_load"]; !ok {
 		t.Error("Statistics missing cpu_load")
 	} else if stat.Avg != 50.0 {
 		t.Errorf("Statistics[cpu_load].Avg = %f, want 50.0", stat.Avg)
@@ -163,7 +163,7 @@ func TestParquetRowToJob(t *testing.T) {
 	if gotData == nil {
 		t.Fatal("JobData is nil")
 	}
-	cpuLoad, ok := (*gotData)["cpu_load"]
+	cpuLoad, ok := (*gotData).Metrics["cpu_load"]
 	if !ok {
 		t.Fatal("JobData missing cpu_load")
 	}
@@ -201,7 +201,7 @@ func TestParquetRowToJobNilOptionalFields(t *testing.T) {
 		},
 	}
 
-	data := &schema.JobData{
+	data := &schema.JobData{Metrics: map[string]schema.ScopedMetrics{
 		"cpu_load": {
 			schema.MetricScopeNode: &schema.JobMetric{
 				Timestep: 60,
@@ -210,7 +210,7 @@ func TestParquetRowToJobNilOptionalFields(t *testing.T) {
 				},
 			},
 		},
-	}
+	}}
 
 	row, err := JobToParquetRow(meta, data)
 	if err != nil {
@@ -228,7 +228,7 @@ func TestParquetRowToJobNilOptionalFields(t *testing.T) {
 	if gotMeta.Tags != nil {
 		t.Errorf("Tags should be nil, got %v", gotMeta.Tags)
 	}
-	if gotMeta.Statistics != nil {
+	if gotMeta.Statistics.Metrics != nil {
 		t.Errorf("Statistics should be nil, got %v", gotMeta.Statistics)
 	}
 	if gotMeta.MetaData != nil {
@@ -299,7 +299,7 @@ func TestRoundTripThroughParquetFile(t *testing.T) {
 	if gotData == nil {
 		t.Fatal("JobData is nil")
 	}
-	if _, ok := (*gotData)["cpu_load"]; !ok {
+	if _, ok := (*gotData).Metrics["cpu_load"]; !ok {
 		t.Error("JobData missing cpu_load")
 	}
 }

pkg/archive/parquet/writer_test.go

@@ -57,7 +57,7 @@ func makeTestJob(jobID int64) (*schema.Job, *schema.JobData) {
 		},
 	}
 
-	data := schema.JobData{
+	data := schema.JobData{Metrics: map[string]schema.ScopedMetrics{
 		"cpu_load": {
 			schema.MetricScopeNode: &schema.JobMetric{
 				Unit:     schema.Unit{Base: ""},
@@ -70,7 +70,7 @@ func makeTestJob(jobID int64) (*schema.Job, *schema.JobData) {
 				},
 			},
 		},
-	}
+	}}
 
 	return meta, &data
 }
@@ -132,7 +132,7 @@ func TestJobToParquetRowConversion(t *testing.T) {
 	if err := json.Unmarshal(decompressed, &jobData); err != nil {
 		t.Fatalf("unmarshal metric data: %v", err)
 	}
-	if _, ok := jobData["cpu_load"]; !ok {
+	if _, ok := jobData.Metrics["cpu_load"]; !ok {
 		t.Error("metric data missing cpu_load key")
 	}
 }

pkg/archive/s3Backend.go

@@ -330,7 +330,7 @@ func (s3a *S3Archive) LoadJobData(job *schema.Job) (schema.JobData, error) {
 		})
 		if err != nil {
 			cclog.Errorf("S3Archive LoadJobData() > GetObject error: %v", err)
-			return nil, err
+			return schema.JobData{}, err
 		}
 		defer result.Body.Close()
 
@@ -349,7 +349,7 @@ func (s3a *S3Archive) LoadJobData(job *schema.Job) (schema.JobData, error) {
 	r, err := gzip.NewReader(result.Body)
 	if err != nil {
 		cclog.Errorf("S3Archive LoadJobData() > gzip error: %v", err)
-		return nil, err
+		return schema.JobData{}, err
 	}
 	defer r.Close()
 
@@ -381,14 +381,14 @@ func (s3a *S3Archive) LoadJobStats(job *schema.Job) (schema.ScopedJobStats, erro
 		})
 		if err != nil {
 			cclog.Errorf("S3Archive LoadJobStats() > GetObject error: %v", err)
-			return nil, err
+			return schema.ScopedJobStats{}, err
 		}
 		defer result.Body.Close()
 
 		if config.Keys.Validate {
 			b, _ := io.ReadAll(result.Body)
 			if err := schema.Validate(schema.Data, bytes.NewReader(b)); err != nil {
-				return nil, fmt.Errorf("validate job data: %v", err)
+				return schema.ScopedJobStats{}, fmt.Errorf("validate job data: %v", err)
 			}
 			return DecodeJobStats(bytes.NewReader(b), key)
 		}
@@ -400,14 +400,14 @@ func (s3a *S3Archive) LoadJobStats(job *schema.Job) (schema.ScopedJobStats, erro
 	r, err := gzip.NewReader(result.Body)
 	if err != nil {
 		cclog.Errorf("S3Archive LoadJobStats() > gzip error: %v", err)
-		return nil, err
+		return schema.ScopedJobStats{}, err
 	}
 	defer r.Close()
 
 	if config.Keys.Validate {
 		b, _ := io.ReadAll(r)
 		if err := schema.Validate(schema.Data, bytes.NewReader(b)); err != nil {
-			return nil, fmt.Errorf("validate job data: %v", err)
+			return schema.ScopedJobStats{}, fmt.Errorf("validate job data: %v", err)
 		}
 		return DecodeJobStats(bytes.NewReader(b), keyGz)
 	}

pkg/archive/sqliteBackend.go

@@ -252,7 +252,7 @@ func (sa *SqliteArchive) LoadJobData(job *schema.Job) (schema.JobData, error) {
 		job.JobID, job.Cluster, job.StartTime).Scan(&dataBlob, &compressed)
 	if err != nil {
 		cclog.Errorf("SqliteArchive LoadJobData() > query error: %v", err)
-		return nil, err
+		return schema.JobData{}, err
 	}
 	key := fmt.Sprintf("%s:%d:%d", job.Cluster, job.JobID, job.StartTime)
 
@@ -261,7 +261,7 @@ func (sa *SqliteArchive) LoadJobData(job *schema.Job) (schema.JobData, error) {
 		gzipReader, err := gzip.NewReader(reader)
 		if err != nil {
 			cclog.Errorf("SqliteArchive LoadJobData() > gzip error: %v", err)
-			return nil, err
+			return schema.JobData{}, err
 		}
 		defer gzipReader.Close()
 		reader = gzipReader
@@ -285,7 +285,7 @@ func (sa *SqliteArchive) LoadJobStats(job *schema.Job) (schema.ScopedJobStats, e
 		job.JobID, job.Cluster, job.StartTime).Scan(&dataBlob, &compressed)
 	if err != nil {
 		cclog.Errorf("SqliteArchive LoadJobStats() > query error: %v", err)
-		return nil, err
+		return schema.ScopedJobStats{}, err
 	}
 	key := fmt.Sprintf("%s:%d:%d", job.Cluster, job.JobID, job.StartTime)
 
@@ -294,7 +294,7 @@ func (sa *SqliteArchive) LoadJobStats(job *schema.Job) (schema.ScopedJobStats, e
 		gzipReader, err := gzip.NewReader(reader)
 		if err != nil {
 			cclog.Errorf("SqliteArchive LoadJobStats() > gzip error: %v", err)
-			return nil, err
+			return schema.ScopedJobStats{}, err
 		}
 		defer gzipReader.Close()
 		reader = gzipReader
@@ -303,7 +303,7 @@ func (sa *SqliteArchive) LoadJobStats(job *schema.Job) (schema.ScopedJobStats, e
 	if config.Keys.Validate {
 		data, _ := io.ReadAll(reader)
 		if err := schema.Validate(schema.Data, bytes.NewReader(data)); err != nil {
-			return nil, fmt.Errorf("validate job data: %v", err)
+			return schema.ScopedJobStats{}, fmt.Errorf("validate job data: %v", err)
 		}
 		return DecodeJobStats(bytes.NewReader(data), key)
 	}

pkg/metricstore/query.go

@@ -89,7 +89,7 @@ func (ccms *InternalMetricStore) LoadData(
 	queries, assignedScope, err := buildQueries(job, metrics, scopes, int64(resolution))
 	if err != nil {
 		cclog.Errorf("Error while building queries for jobId %d, Metrics %v, Scopes %v: %s", job.JobID, metrics, scopes, err.Error())
-		return nil, err
+		return schema.JobData{}, err
 	}
 
 	// Verify assignment is correct - log any inconsistencies for debugging
@@ -110,11 +110,11 @@ func (ccms *InternalMetricStore) LoadData(
 	resBody, err := FetchData(req)
 	if err != nil {
 		cclog.Errorf("Error while fetching data : %s", err.Error())
-		return nil, err
+		return schema.JobData{}, err
 	}
 
 	var errors []string
-	jobData := make(schema.JobData)
+	jobData := schema.JobData{Metrics: make(map[string]schema.ScopedMetrics)}
 
 	// Add safety check for potential index out of range errors
 	if len(resBody.Results) != len(req.Queries) || len(assignedScope) != len(req.Queries) {
@@ -139,8 +139,8 @@ func (ccms *InternalMetricStore) LoadData(
 			continue
 		}
 
-		if _, ok := jobData[metric]; !ok {
-			jobData[metric] = make(map[schema.MetricScope]*schema.JobMetric)
+		if _, ok := jobData.Metrics[metric]; !ok {
+			jobData.Metrics[metric] = make(schema.ScopedMetrics)
 		}
 
 		res := mc.Timestep
@@ -148,14 +148,14 @@ func (ccms *InternalMetricStore) LoadData(
 			res = int(row[0].Resolution)
 		}
 
-		jobMetric, ok := jobData[metric][scope]
+		jobMetric, ok := jobData.Metrics[metric][scope]
 		if !ok {
 			jobMetric = &schema.JobMetric{
 				Unit:     mc.Unit,
 				Timestep: res,
 				Series:   make([]schema.Series, 0),
 			}
-			jobData[metric][scope] = jobMetric
+			jobData.Metrics[metric][scope] = jobMetric
 		}
 
 		for ndx, res := range row {
@@ -183,9 +183,9 @@ func (ccms *InternalMetricStore) LoadData(
 
 		// So that one can later check len(jobData):
 		if len(jobMetric.Series) == 0 {
-			delete(jobData[metric], scope)
-			if len(jobData[metric]) == 0 {
-				delete(jobData, metric)
+			delete(jobData.Metrics[metric], scope)
+			if len(jobData.Metrics[metric]) == 0 {
+				delete(jobData.Metrics, metric)
 			}
 		}
 	}
@@ -407,7 +407,7 @@ func (ccms *InternalMetricStore) LoadScopedStats(
 	queries, assignedScope, err := buildQueries(job, metrics, scopes, 0)
 	if err != nil {
 		cclog.Errorf("Error while building queries for jobId %d, Metrics %v, Scopes %v: %s", job.JobID, metrics, scopes, err.Error())
-		return nil, err
+		return schema.ScopedJobStats{}, err
 	}
 
 	req := APIQueryRequest{
@@ -422,11 +422,11 @@ func (ccms *InternalMetricStore) LoadScopedStats(
 	resBody, err := FetchData(req)
 	if err != nil {
 		cclog.Errorf("Error while fetching data : %s", err.Error())
-		return nil, err
+		return schema.ScopedJobStats{}, err
 	}
 
 	var errors []string
-	scopedJobStats := make(schema.ScopedJobStats)
+	scopedJobStats := schema.ScopedJobStats{Metrics: make(map[string]schema.ScopedMetricStats)}
 
 	for i, row := range resBody.Results {
 		if len(row) == 0 {
@@ -437,12 +437,12 @@ func (ccms *InternalMetricStore) LoadScopedStats(
 		metric := query.Metric
 		scope := assignedScope[i]
 
-		if _, ok := scopedJobStats[metric]; !ok {
-			scopedJobStats[metric] = make(map[schema.MetricScope][]*schema.ScopedStats)
+		if _, ok := scopedJobStats.Metrics[metric]; !ok {
+			scopedJobStats.Metrics[metric] = make(schema.ScopedMetricStats)
 		}
 
-		if _, ok := scopedJobStats[metric][scope]; !ok {
-			scopedJobStats[metric][scope] = make([]*schema.ScopedStats, 0)
+		if _, ok := scopedJobStats.Metrics[metric][scope]; !ok {
+			scopedJobStats.Metrics[metric][scope] = make([]*schema.ScopedStats, 0)
 		}
 
 		for ndx, res := range row {
@@ -456,7 +456,7 @@ func (ccms *InternalMetricStore) LoadScopedStats(
 
 			SanitizeStats(&res.Avg, &res.Min, &res.Max)
 
-			scopedJobStats[metric][scope] = append(scopedJobStats[metric][scope], &schema.ScopedStats{
+			scopedJobStats.Metrics[metric][scope] = append(scopedJobStats.Metrics[metric][scope], &schema.ScopedStats{
 				Hostname: query.Hostname,
 				ID:       id,
 				Data: &schema.MetricStatistics{
@@ -467,11 +467,11 @@ func (ccms *InternalMetricStore) LoadScopedStats(
 			})
 		}
 
-		// So that one can later check len(scopedJobStats[metric][scope]): Remove from map if empty
-		if len(scopedJobStats[metric][scope]) == 0 {
-			delete(scopedJobStats[metric], scope)
-			if len(scopedJobStats[metric]) == 0 {
-				delete(scopedJobStats, metric)
+		// So that one can later check len(scopedJobStats.Metrics[metric][scope]): Remove from map if empty
+		if len(scopedJobStats.Metrics[metric][scope]) == 0 {
+			delete(scopedJobStats.Metrics[metric], scope)
+			if len(scopedJobStats.Metrics[metric]) == 0 {
+				delete(scopedJobStats.Metrics, metric)
 			}
 		}
 	}
@@ -695,14 +695,14 @@ func (ccms *InternalMetricStore) LoadNodeListData(
 		// Init Nested Map Data Structures If Not Found
 		hostData, ok := data[query.Hostname]
 		if !ok {
-			hostData = make(schema.JobData)
+			hostData = schema.JobData{Metrics: make(map[string]schema.ScopedMetrics)}
 			data[query.Hostname] = hostData
 		}
 
-		metricData, ok := hostData[metric]
+		metricData, ok := hostData.Metrics[metric]
 		if !ok {
-			metricData = make(map[schema.MetricScope]*schema.JobMetric)
-			data[query.Hostname][metric] = metricData
+			metricData = make(schema.ScopedMetrics)
+			data[query.Hostname].Metrics[metric] = metricData
 		}
 
 		scopeData, ok := metricData[scope]
@@ -712,7 +712,7 @@ func (ccms *InternalMetricStore) LoadNodeListData(
 				Timestep: res,
 				Series:   make([]schema.Series, 0),
 			}
-			data[query.Hostname][metric][scope] = scopeData
+			data[query.Hostname].Metrics[metric][scope] = scopeData
 		}
 
 		for ndx, res := range row {