Added new implementation that makes the distributor accept multiple HA pairs (cluster, replica) in the same requets/batch. This can be enabled with a new flag, accept_mixed_ha_samples, an will take effect only if accept_ha_samples is set to true.

Fixed test by reducing the number of ingesters to 2 and replication factor to 2.

Added config reference.

Do not remove replica label if cluster label is not present.

Added more HA mixed replicas tests with no cluster and replica labels and with cluster label only.

Signed-off-by: eduardscaueru <[email protected]>

Author: eduardscaueru

CHANGELOG.md

@@ -9,6 +9,7 @@
 * [FEATURE] Ruler: Minimize chances of missed rule group evaluations that can occur due to OOM kills, bad underlying nodes, or due to an unhealthy ruler that appears in the ring as healthy. This feature is enabled via `-ruler.enable-ha-evaluation` flag. #6129
 * [FEATURE] Store Gateway: Add an in-memory chunk cache. #6245
 * [FEATURE] Chunk Cache: Support multi level cache and add metrics. #6249
+* [FEATURE] Distributor: Accept multiple HA Tracker pairs in the same request. #6256
 * [ENHANCEMENT] Ingester: Add `blocks-storage.tsdb.wal-compression-type` to support zstd wal compression type. #6232
 * [ENHANCEMENT] Query Frontend: Add info field to query response. #6207
 * [ENHANCEMENT] Query Frontend: Add peakSample in query stats response. #6188

docs/configuration/config-file-reference.md

@@ -3163,6 +3163,12 @@ The `limits_config` configures default and per-tenant limits imposed by Cortex s
 # CLI flag: -distributor.ha-tracker.enable-for-all-users
 [accept_ha_samples: <boolean> | default = false]
 
+# Flag to enable handling of samples with mixed external labels identifying
+# replicas in an HA Prometheus setup. Supported only if
+# -distributor.ha-tracker.enable-for-all-users is true.
+# CLI flag: -distributor.ha-tracker.mixed-ha-samples
+[accept_mixed_ha_samples: <boolean> | default = false]
+
 # Prometheus label to look for in samples to identify a Prometheus HA cluster.
 # CLI flag: -distributor.ha-tracker.cluster
 [ha_cluster_label: <string> | default = "cluster"]

pkg/distributor/distributor.go

@@ -652,7 +652,7 @@ func (d *Distributor) Push(ctx context.Context, req *cortexpb.WriteRequest) (*co
 	// Cache user limit with overrides so we spend less CPU doing locking. See issue #4904
 	limits := d.limits.GetOverridesForUser(userID)
 
-	if limits.AcceptHASamples && len(req.Timeseries) > 0 {
+	if limits.AcceptHASamples && len(req.Timeseries) > 0 && !limits.AcceptMixedHASamples {
 		cluster, replica := findHALabels(limits.HAReplicaLabel, limits.HAClusterLabel, req.Timeseries[0].Labels)
 		removeReplica, err = d.checkSample(ctx, userID, cluster, replica, limits)
 		if err != nil {
@@ -676,6 +676,8 @@ func (d *Distributor) Push(ctx context.Context, req *cortexpb.WriteRequest) (*co
 		if !removeReplica { // False, Nil
 			d.nonHASamples.WithLabelValues(userID).Add(float64(numFloatSamples + numHistogramSamples))
 		}
+	} else if limits.AcceptHASamples && len(req.Timeseries) > 0 && limits.AcceptMixedHASamples {
+		removeReplica = true
 	}
 
 	// A WriteRequest can only contain series or metadata but not both. This might change in the future.
@@ -859,6 +861,19 @@ func (d *Distributor) prepareSeriesKeys(ctx context.Context, req *cortexpb.Write
 	// check each sample and discard if outside limits.
 	skipLabelNameValidation := d.cfg.SkipLabelNameValidation || req.GetSkipLabelNameValidation()
 	for _, ts := range req.Timeseries {
+		removeReplicaTs := removeReplica
+		if limits.AcceptHASamples && limits.AcceptMixedHASamples {
+			validCode, cluster := d.isValidHAPair(ts.Labels, ctx, userID, limits)
+			if validCode == 1 {
+				d.dedupedSamples.WithLabelValues(userID, cluster).Add(float64(len(ts.Samples) + len(ts.Histograms)))
+				continue
+			} else if validCode == 2 {
+				removeReplicaTs = false
+				d.nonHASamples.WithLabelValues(userID).Add(float64(len(ts.Samples) + len(ts.Histograms)))
+			} else if validCode == 0 {
+				removeReplicaTs = true
+			}
+		}
 		// Use timestamp of latest sample in the series. If samples for series are not ordered, metric for user may be wrong.
 		if len(ts.Samples) > 0 {
 			latestSampleTimestampMs = max(latestSampleTimestampMs, ts.Samples[len(ts.Samples)-1].TimestampMs)
@@ -889,7 +904,7 @@ func (d *Distributor) prepareSeriesKeys(ctx context.Context, req *cortexpb.Write
 		// If we found both the cluster and replica labels, we only want to include the cluster label when
 		// storing series in Cortex. If we kept the replica label we would end up with another series for the same
 		// series we're trying to dedupe when HA tracking moves over to a different replica.
-		if removeReplica {
+		if removeReplicaTs {
 			removeLabel(limits.HAReplicaLabel, &ts.Labels)
 		}
 
@@ -1467,6 +1482,19 @@ func findHALabels(replicaLabel, clusterLabel string, labels []cortexpb.LabelAdap
 	return cluster, replica
 }
 
+func (d *Distributor) isValidHAPair(labels []cortexpb.LabelAdapter, ctx context.Context, userID string, limits *validation.Limits) (int, string) {
+	cluster, replica := findHALabels(limits.HAReplicaLabel, limits.HAClusterLabel, labels)
+
+	if cluster != "" && replica != "" {
+		_, err := d.checkSample(ctx, userID, cluster, replica, limits)
+		if err != nil {
+			return 1, cluster // discard sample
+		}
+		return 0, cluster // valid HA sample
+	}
+	return 2, cluster // non HA sample
+}
+
 func getLimitFromLabelHints(hints *storage.LabelHints) int {
 	if hints != nil {
 		return hints.Limit

pkg/distributor/distributor_test.go

@@ -1031,6 +1031,102 @@ func TestDistributor_PushHAInstances(t *testing.T) {
 	}
 }
 
+func TestDistributor_PushMixedHAInstances(t *testing.T) {
+	t.Parallel()
+	ctx := user.InjectOrgID(context.Background(), "user")
+
+	for i, tc := range []struct {
+		enableTracker        bool
+		acceptMixedHASamples bool
+		samples              int
+		expectedResponse     *cortexpb.WriteResponse
+		expectedCode         int32
+	}{
+		{
+			enableTracker:        true,
+			acceptMixedHASamples: true,
+			samples:              5,
+			expectedResponse:     emptyResponse,
+			expectedCode:         202,
+		},
+	} {
+		for _, shardByAllLabels := range []bool{true} {
+			tc := tc
+			shardByAllLabels := shardByAllLabels
+			for _, enableHistogram := range []bool{false} {
+				enableHistogram := enableHistogram
+				t.Run(fmt.Sprintf("[%d](shardByAllLabels=%v, histogram=%v)", i, shardByAllLabels, enableHistogram), func(t *testing.T) {
+					t.Parallel()
+					var limits validation.Limits
+					flagext.DefaultValues(&limits)
+					limits.AcceptHASamples = true
+					limits.AcceptMixedHASamples = tc.acceptMixedHASamples
+					limits.MaxLabelValueLength = 25
+
+					ds, ingesters, _, _ := prepare(t, prepConfig{
+						numIngesters:      2,
+						happyIngesters:    2,
+						numDistributors:   1,
+						replicationFactor: 2,
+						shardByAllLabels:  shardByAllLabels,
+						limits:            &limits,
+						enableTracker:     tc.enableTracker,
+					})
+
+					d := ds[0]
+
+					request := makeWriteRequestHAMixedSamples(tc.samples, enableHistogram)
+					response, _ := d.Push(ctx, request)
+					assert.Equal(t, tc.expectedResponse, response)
+
+					for i := range ingesters {
+						timeseries := ingesters[i].series()
+						assert.Equal(t, 5, len(timeseries))
+						clusters := make(map[string]int)
+						replicas := make(map[string]int)
+						for _, v := range timeseries {
+							replicaLabel := ""
+							clusterLabel := ""
+							for _, label := range v.Labels {
+								if label.Name == "__replica__" {
+									replicaLabel = label.Value
+									_, ok := replicas[label.Value]
+									if !ok {
+										replicas[label.Value] = 1
+									} else {
+										assert.Fail(t, fmt.Sprintf("Two timeseries with same replica label, %s, were found, but only one should be present", label.Value))
+									}
+								}
+								if label.Name == "cluster" {
+									clusterLabel = label.Value
+									_, ok := clusters[label.Value]
+									if !ok {
+										clusters[label.Value] = 1
+									} else {
+										assert.Fail(t, fmt.Sprintf("Two timeseries with same cluster label, %s, were found, but only one should be present", label.Value))
+									}
+								}
+							}
+							if clusterLabel == "" && replicaLabel != "" {
+								assert.Equal(t, "replicaNoCluster", replicaLabel)
+							}
+							assert.Equal(t, tc.samples, len(v.Samples))
+						}
+						assert.Equal(t, 3, len(clusters))
+						for _, nr := range clusters {
+							assert.Equal(t, true, nr == 1)
+						}
+						assert.Equal(t, 1, len(replicas))
+						for _, nr := range clusters {
+							assert.Equal(t, true, nr == 1)
+						}
+					}
+				})
+			}
+		}
+	}
+}
+
 func TestDistributor_PushQuery(t *testing.T) {
 	t.Parallel()
 	const shuffleShardSize = 5
@@ -2831,7 +2927,7 @@ func prepare(tb testing.TB, cfg prepConfig) ([]*Distributor, []*mockIngester, []
 				EnableHATracker: true,
 				KVStore:         kv.Config{Mock: mock},
 				UpdateTimeout:   100 * time.Millisecond,
-				FailoverTimeout: time.Second,
+				FailoverTimeout: time.Hour,
 			}
 			cfg.limits.HAMaxClusters = 100
 		}
@@ -2950,6 +3046,106 @@ func makeWriteRequestHA(samples int, replica, cluster string, histogram bool) *c
 	return request
 }
 
+func makeWriteRequestHAMixedSamples(samples int, histogram bool) *cortexpb.WriteRequest {
+	request := &cortexpb.WriteRequest{}
+
+	for _, haPair := range []struct {
+		cluster string
+		replica string
+	}{
+		{
+			cluster: "cluster0",
+			replica: "replica0",
+		},
+		{
+			cluster: "cluster0",
+			replica: "replica1",
+		},
+		{
+			cluster: "cluster1",
+			replica: "replica0",
+		},
+		{
+			cluster: "cluster1",
+			replica: "replica1",
+		},
+		{
+			cluster: "",
+			replica: "replicaNoCluster",
+		},
+		{
+			cluster: "clusterNoReplica",
+			replica: "",
+		},
+		{
+			cluster: "",
+			replica: "",
+		},
+	} {
+		cluster := haPair.cluster
+		replica := haPair.replica
+		var ts cortexpb.PreallocTimeseries
+		if cluster == "" && replica == "" {
+			ts = cortexpb.PreallocTimeseries{
+				TimeSeries: &cortexpb.TimeSeries{
+					Labels: []cortexpb.LabelAdapter{
+						{Name: "__name__", Value: "foo"},
+						{Name: "bar", Value: "baz"},
+					},
+				},
+			}
+		} else if cluster == "" && replica != "" {
+			ts = cortexpb.PreallocTimeseries{
+				TimeSeries: &cortexpb.TimeSeries{
+					Labels: []cortexpb.LabelAdapter{
+						{Name: "__name__", Value: "foo"},
+						{Name: "__replica__", Value: replica},
+						{Name: "bar", Value: "baz"},
+					},
+				},
+			}
+		} else if cluster != "" && replica == "" {
+			ts = cortexpb.PreallocTimeseries{
+				TimeSeries: &cortexpb.TimeSeries{
+					Labels: []cortexpb.LabelAdapter{
+						{Name: "__name__", Value: "foo"},
+						{Name: "bar", Value: "baz"},
+						{Name: "cluster", Value: cluster},
+					},
+				},
+			}
+		} else {
+			ts = cortexpb.PreallocTimeseries{
+				TimeSeries: &cortexpb.TimeSeries{
+					Labels: []cortexpb.LabelAdapter{
+						{Name: "__name__", Value: "foo"},
+						{Name: "__replica__", Value: replica},
+						{Name: "bar", Value: "baz"},
+						{Name: "cluster", Value: cluster},
+					},
+				},
+			}
+		}
+		if histogram {
+			ts.Histograms = []cortexpb.Histogram{
+				cortexpb.HistogramToHistogramProto(int64(samples), tsdbutil.GenerateTestHistogram(samples)),
+			}
+		} else {
+			var s = make([]cortexpb.Sample, 0)
+			for i := 0; i < samples; i++ {
+				sample := cortexpb.Sample{
+					Value:       float64(i),
+					TimestampMs: int64(i),
+				}
+				s = append(s, sample)
+			}
+			ts.Samples = s
+		}
+		request.Timeseries = append(request.Timeseries, ts)
+	}
+	return request
+}
+
 func makeWriteRequestExemplar(seriesLabels []string, timestamp int64, exemplarLabels []string) *cortexpb.WriteRequest {
 	return &cortexpb.WriteRequest{
 		Timeseries: []cortexpb.PreallocTimeseries{

pkg/util/validation/limits.go

@@ -119,6 +119,7 @@ type Limits struct {
 	IngestionRateStrategy     string              `yaml:"ingestion_rate_strategy" json:"ingestion_rate_strategy"`
 	IngestionBurstSize        int                 `yaml:"ingestion_burst_size" json:"ingestion_burst_size"`
 	AcceptHASamples           bool                `yaml:"accept_ha_samples" json:"accept_ha_samples"`
+	AcceptMixedHASamples      bool                `yaml:"accept_mixed_ha_samples" json:"accept_mixed_ha_samples"`
 	HAClusterLabel            string              `yaml:"ha_cluster_label" json:"ha_cluster_label"`
 	HAReplicaLabel            string              `yaml:"ha_replica_label" json:"ha_replica_label"`
 	HAMaxClusters             int                 `yaml:"ha_max_clusters" json:"ha_max_clusters"`
@@ -220,6 +221,7 @@ func (l *Limits) RegisterFlags(f *flag.FlagSet) {
 	f.StringVar(&l.IngestionRateStrategy, "distributor.ingestion-rate-limit-strategy", "local", "Whether the ingestion rate limit should be applied individually to each distributor instance (local), or evenly shared across the cluster (global).")
 	f.IntVar(&l.IngestionBurstSize, "distributor.ingestion-burst-size", 50000, "Per-user allowed ingestion burst size (in number of samples).")
 	f.BoolVar(&l.AcceptHASamples, "distributor.ha-tracker.enable-for-all-users", false, "Flag to enable, for all users, handling of samples with external labels identifying replicas in an HA Prometheus setup.")
+	f.BoolVar(&l.AcceptMixedHASamples, "distributor.ha-tracker.mixed-ha-samples", false, "Flag to enable handling of samples with mixed external labels identifying replicas in an HA Prometheus setup. Supported only if -distributor.ha-tracker.enable-for-all-users is true.")
 	f.StringVar(&l.HAClusterLabel, "distributor.ha-tracker.cluster", "cluster", "Prometheus label to look for in samples to identify a Prometheus HA cluster.")
 	f.StringVar(&l.HAReplicaLabel, "distributor.ha-tracker.replica", "__replica__", "Prometheus label to look for in samples to identify a Prometheus HA replica.")
 	f.IntVar(&l.HAMaxClusters, "distributor.ha-tracker.max-clusters", 0, "Maximum number of clusters that HA tracker will keep track of for single user. 0 to disable the limit.")
@@ -547,6 +549,11 @@ func (o *Overrides) AcceptHASamples(userID string) bool {
 	return o.GetOverridesForUser(userID).AcceptHASamples
 }
 
+// AcceptMixedHASamples returns whether the distributor should track and accept mixed samples from HA replicas for this user.
+func (o *Overrides) AcceptMixedHASamples(userID string) bool {
+	return o.GetOverridesForUser(userID).AcceptMixedHASamples
+}
+
 // HAClusterLabel returns the cluster label to look for when deciding whether to accept a sample from a Prometheus HA replica.
 func (o *Overrides) HAClusterLabel(userID string) string {
 	return o.GetOverridesForUser(userID).HAClusterLabel