New version of GetRef() that returns labels

Now we only need to make a copy if GetRef() returns zero

Note Prometheus update brings in JSON marshalling of model.Duration
prometheus/common#280

Signed-off-by: Bryan Boreham <[email protected]>

Author: bboreham

go.mod

@@ -46,8 +46,8 @@ require (
 	github.com/prometheus/alertmanager v0.21.1-0.20210310093010-0f9cab6991e6
 	github.com/prometheus/client_golang v1.9.0
 	github.com/prometheus/client_model v0.2.0
-	github.com/prometheus/common v0.18.0
-	github.com/prometheus/prometheus v1.8.2-0.20210319192855-d614ae9ecf1c
+	github.com/prometheus/common v0.20.0
+	github.com/prometheus/prometheus v1.8.2-0.20210321183757-31a518faab18
 	github.com/segmentio/fasthash v0.0.0-20180216231524-a72b379d632e
 	github.com/sony/gobreaker v0.4.1
 	github.com/spf13/afero v1.2.2
@@ -101,3 +101,15 @@ replace github.com/go-openapi/strfmt => github.com/go-openapi/strfmt v0.19.5
 replace github.com/go-openapi/swag => github.com/go-openapi/swag v0.19.9
 
 replace github.com/go-openapi/validate => github.com/go-openapi/validate v0.19.8
+
+// Branch for testing
+replace github.com/prometheus/prometheus => github.com/bboreham/prometheus v1.7.2-0.20210323212203-73930f5e682c
+
+// Pin these otherwise they downgrade
+replace go.mongodb.org/mongo-driver => go.mongodb.org/mongo-driver v1.3.2
+
+replace github.com/mitchellh/mapstructure => github.com/mitchellh/mapstructure v1.2.2
+
+replace github.com/hashicorp/go-hclog => github.com/hashicorp/go-hclog v0.12.2
+
+replace github.com/hashicorp/go-immutable-radix => github.com/hashicorp/go-immutable-radix v1.2.0

go.sum

@@ -197,6 +197,8 @@ github.com/aws/aws-sdk-go v1.37.8/go.mod h1:hcU610XS61/+aQV88ixoOzUoG7v3b31pl2zK
 github.com/aws/aws-sdk-go-v2 v0.18.0/go.mod h1:JWVYvqSMppoMJC0x5wdwiImzgXTI9FuZwxzkQq9wy+g=
 github.com/baiyubin/aliyun-sts-go-sdk v0.0.0-20180326062324-cfa1a18b161f h1:ZNv7On9kyUzm7fvRZumSyy/IUiSC7AzL0I1jKKtwooA=
 github.com/baiyubin/aliyun-sts-go-sdk v0.0.0-20180326062324-cfa1a18b161f/go.mod h1:AuiFmCCPBSrqvVMvuqFuk0qogytodnVFVSN5CeJB8Gc=
+github.com/bboreham/prometheus v1.7.2-0.20210323212203-73930f5e682c h1:rnzCAKpqQJ0Imp9D2lpqB4ZPypZKEZ7Dj0AQ26gOPrM=
+github.com/bboreham/prometheus v1.7.2-0.20210323212203-73930f5e682c/go.mod h1:QXavF3rQy2C4kfRg+O+44fkSXg2ADPVfXPCRKwTmbAk=
 github.com/beevik/ntp v0.2.0/go.mod h1:hIHWr+l3+/clUnF44zdK+CWW7fO8dR5cIylAQ76NRpg=
 github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24TaqPxmxbtue+5NUziq4I4S80YR8gNf3Q=
 github.com/beorn7/perks v1.0.0/go.mod h1:KWe93zE9D1o94FZ5RNwFwVgaQK1VOXiVxmqh+CedLV8=
@@ -1067,6 +1069,8 @@ github.com/prometheus/common v0.14.0/go.mod h1:U+gB1OBLb1lF3O42bTCL+FK18tX9Oar16
 github.com/prometheus/common v0.15.0/go.mod h1:U+gB1OBLb1lF3O42bTCL+FK18tX9Oar16Clt/msog/s=
 github.com/prometheus/common v0.18.0 h1:WCVKW7aL6LEe1uryfI9dnEc2ZqNB1Fn0ok930v0iL1Y=
 github.com/prometheus/common v0.18.0/go.mod h1:U+gB1OBLb1lF3O42bTCL+FK18tX9Oar16Clt/msog/s=
+github.com/prometheus/common v0.20.0 h1:pfeDeUdQcIxOMutNjCejsEFp7qeP+/iltHSSmLpE+hU=
+github.com/prometheus/common v0.20.0/go.mod h1:U+gB1OBLb1lF3O42bTCL+FK18tX9Oar16Clt/msog/s=
 github.com/prometheus/exporter-toolkit v0.5.0/go.mod h1:OCkM4805mmisBhLmVFw858QYi3v0wKdY6/UxrT0pZVg=
 github.com/prometheus/exporter-toolkit v0.5.1/go.mod h1:OCkM4805mmisBhLmVFw858QYi3v0wKdY6/UxrT0pZVg=
 github.com/prometheus/node_exporter v1.0.0-rc.0.0.20200428091818-01054558c289 h1:dTUS1vaLWq+Y6XKOTnrFpoVsQKLCbCp1OLj24TDi7oM=

pkg/ingester/ingester_v2.go

@@ -724,15 +724,11 @@ func (i *Ingester) v2Push(ctx context.Context, req *cortexpb.WriteRequest) (*cor
 	// Walk the samples, appending them to the users database
 	app := db.Appender(ctx).(extendedAppender)
 	for _, ts := range req.Timeseries {
-		// Keeps a reference to labels copy, if it was needed. This is to avoid making a copy twice,
-		// once for TSDB, and second time for activeSeries map.
-		var copiedLabels []labels.Label
-
 		// The labels must be sorted (in our case, it's guaranteed a write request
 		// has sorted labels once hit the ingester).
 
-		// Look up a reference for this series. Holding the appendLock ensures that no compaction will happen while we use it.
-		ref := app.GetRef(cortexpb.FromLabelAdaptersToLabels(ts.Labels))
+		// Look up a reference for this series.
+		ref, copiedLabels := app.GetRef(cortexpb.FromLabelAdaptersToLabels(ts.Labels))
 
 		// To find out if any sample was added to this series, we keep old value.
 		oldSucceededSamplesCount := succeededSamplesCount
@@ -742,14 +738,13 @@ func (i *Ingester) v2Push(ctx context.Context, req *cortexpb.WriteRequest) (*cor
 
 			// If the cached reference exists, we try to use it.
 			if ref != 0 {
-				labels := cortexpb.FromLabelAdaptersToLabels(ts.Labels)
-				if _, err = app.Append(ref, labels, s.TimestampMs, s.Value); err == nil {
+				if _, err = app.Append(ref, copiedLabels, s.TimestampMs, s.Value); err == nil {
 					succeededSamplesCount++
 					continue
 				}
 
 			} else {
-				// Copy the label set because both TSDB and the cache may retain it.
+				// Copy the label set because both TSDB and the active series tracker may retain it.
 				copiedLabels = cortexpb.FromLabelAdaptersToLabelsWithCopy(ts.Labels)
 
 				// Retain the reference in case there are multiple samples for the series.
@@ -789,9 +784,6 @@ func (i *Ingester) v2Push(ctx context.Context, req *cortexpb.WriteRequest) (*cor
 			case errMaxSeriesPerMetricLimitExceeded:
 				perMetricSeriesLimitCount++
 				updateFirstPartial(func() error {
-					if copiedLabels == nil {
-						copiedLabels = cortexpb.FromLabelAdaptersToLabelsWithCopy(ts.Labels)
-					}
 					return makeMetricLimitError(perMetricSeriesLimit, copiedLabels, i.limiter.FormatError(userID, cause))
 				})
 				continue
@@ -807,11 +799,7 @@ func (i *Ingester) v2Push(ctx context.Context, req *cortexpb.WriteRequest) (*cor
 
 		if i.cfg.ActiveSeriesMetricsEnabled && succeededSamplesCount > oldSucceededSamplesCount {
 			db.activeSeries.UpdateSeries(cortexpb.FromLabelAdaptersToLabels(ts.Labels), startAppend, func(l labels.Labels) labels.Labels {
-				// If we have already made a copy during this push, no need to create new one.
-				if copiedLabels != nil {
-					return copiedLabels
-				}
-				return cortexpb.CopyLabels(l)
+				return copiedLabels
 			})
 		}
 	}