Added changes to enable and disable the examplers storage

Description: Added changes to enable and disable the examplers storage

Signed-off-by: hiteshwani29 <hiteshwani29@gmail.com>

CHANGELOG.md

@@ -14,6 +14,7 @@ We use *breaking :warning:* to mark changes that are not backward compatible (re
 
 - [#6185](https://github.com/thanos-io/thanos/pull/6185) Tracing: tracing in OTLP support configuring service_name.
 - [#6192](https://github.com/thanos-io/thanos/pull/6192) Store: add flag `bucket-web-label` to select the label to use as timeline title in web UI
+- [#6216](https://github.com/thanos-io/thanos/pull/6216) Receiver: add flag `tsdb.enable-exemplar-storage` to enable exemplar storage
 
 ### Fixed
 

cmd/thanos/receive.go

@@ -76,6 +76,13 @@ func registerReceive(app *extkingpin.App) {
 			return errors.Wrap(err, "error while parsing config for request logging")
 		}
 
+		if !conf.tsdbEnableExemplarStorage && conf.tsdbMaxExemplars > 0 {
+			return errors.New("Enable tsdb.enable-exemplars-storage flag to pass tsdb.max-exemplars ")
+		}
+		if conf.tsdbEnableExemplarStorage && conf.tsdbMaxExemplars <= 0 {
+			return errors.New("tsdb.enable-exemplars-storage flag is enabled, value of tsdb.max-exemplars must be > 0")
+		}
+
 		tsdbOpts := &tsdb.Options{
 			MinBlockDuration:               int64(time.Duration(*conf.tsdbMinBlockDuration) / time.Millisecond),
 			MaxBlockDuration:               int64(time.Duration(*conf.tsdbMaxBlockDuration) / time.Millisecond),
@@ -85,7 +92,7 @@ func registerReceive(app *extkingpin.App) {
 			NoLockfile:                     conf.noLockFile,
 			WALCompression:                 conf.walCompression,
 			MaxExemplars:                   conf.tsdbMaxExemplars,
-			EnableExemplarStorage:          true,
+			EnableExemplarStorage:          conf.tsdbEnableExemplarStorage,
 			HeadChunksWriteQueueSize:       int(conf.tsdbWriteQueueSize),
 			EnableMemorySnapshotOnShutdown: conf.tsdbMemorySnapshotOnShutdown,
 			EnableNativeHistograms:         conf.tsdbEnableNativeHistograms,
@@ -781,6 +788,7 @@ type receiveConfig struct {
 	tsdbWriteQueueSize           int64
 	tsdbMemorySnapshotOnShutdown bool
 	tsdbEnableNativeHistograms   bool
+	tsdbEnableExemplarStorage    bool
 
 	walCompression  bool
 	noLockFile      bool
@@ -879,6 +887,8 @@ func (rc *receiveConfig) registerFlag(cmd extkingpin.FlagClause) {
 
 	cmd.Flag("tsdb.wal-compression", "Compress the tsdb WAL.").Default("true").BoolVar(&rc.walCompression)
 
+	cmd.Flag("tsdb.enable-exemplar-storage", "Enables support for exemplar storage.").Default("false").BoolVar(&rc.tsdbEnableExemplarStorage)
+
 	cmd.Flag("tsdb.no-lockfile", "Do not create lockfile in TSDB data directory. In any case, the lockfiles will be deleted on next startup.").Default("false").BoolVar(&rc.noLockFile)
 
 	cmd.Flag("tsdb.max-exemplars",

docs/components/receive.md

@@ -6,7 +6,7 @@ We recommend this component to users who can only push into a Thanos due to air-
 
 Thanos Receive supports multi-tenancy by using labels. See [Multi-tenancy documentation here](../operating/multi-tenancy.md).
 
-Thanos Receive supports ingesting [exemplars](https://github.com/OpenObservability/OpenMetrics/blob/main/specification/OpenMetrics.md#exemplars) via remote-write. By default, the exemplars are silently discarded as `--tsdb.max-exemplars` is set to `0`. To enable exemplars storage, set the `--tsdb.max-exemplars` flag to a non-zero value. It exposes the ExemplarsAPI so that the [Thanos Queriers](query.md) can query the stored exemplars. Take a look at the documentation for [exemplars storage in Prometheus](https://prometheus.io/docs/prometheus/latest/disabled_features/#exemplars-storage) to know more about it.
+Thanos Receive supports ingesting [exemplars](https://github.com/OpenObservability/OpenMetrics/blob/main/specification/OpenMetrics.md#exemplars) via remote-write. By default, the exemplars are silently discarded as `--tsdb.max-exemplars` is set to `0`. To enable exemplars storage, set the `--tsdb.max-exemplars` flag to a non-zero value and enable --tsdb.enable-exemplars-storage flag . It exposes the ExemplarsAPI so that the [Thanos Queriers](query.md) can query the stored exemplars. Take a look at the documentation for [exemplars storage in Prometheus](https://prometheus.io/docs/prometheus/latest/disabled_features/#exemplars-storage) to know more about it.
 
 For more information please check out [initial design proposal](../proposals-done/201812-thanos-remote-receive.md). For further information on tuning Prometheus Remote Write [see remote write tuning document](https://prometheus.io/docs/practices/remote_write/).
 
@@ -376,6 +376,8 @@ Flags:
                                  Allow overlapping blocks, which in turn enables
                                  vertical compaction and vertical query merge.
                                  Does not do anything, enabled all the time.
+      --tsdb.enable-exemplar-storage
+                                 Enables support for exemplar storage.
       --tsdb.max-exemplars=0     Enables support for ingesting exemplars and
                                  sets the maximum number of exemplars that will
                                  be stored per tenant. In case the exemplar