Fix out of order exemplar error for native histograms

CHANGELOG.md

@@ -11,6 +11,7 @@
 * [BUGFIX] Ingester: Prevent timely compaction of empty blocks. #7624
 * [BUGFIX] querier: Don't cache context.Canceled errors for bucket index. #7620
 * [BUGFIX] Store-gateway: account for `"other"` time in LabelValues and LabelNames requests. #7622
+* [BUGFIX] Ingester: when receiving multiple exemplars for a native histogram in mimir via remote write, only report an error if all are older than the latest exemplar as this could be a partial update. #7640
 
 ### Mixin
 

pkg/ingester/ingester.go

@@ -1399,6 +1399,7 @@ func (i *Ingester) pushSamplesToAppender(userID string, timeseries []mimirpb.Pre
 				})
 				stats.failedExemplarsCount += len(ts.Exemplars)
 			} else { // Note that else is explicit, rather than a continue in the above if, in case of additional logic post exemplar processing.
+				outOfOrderExemplars := 0
 				for _, ex := range ts.Exemplars {
 					if ex.TimestampMs > maxTimestampMs {
 						stats.failedExemplarsCount++
@@ -1421,6 +1422,15 @@ func (i *Ingester) pushSamplesToAppender(userID string, timeseries []mimirpb.Pre
 						continue
 					}
 
+					if errors.Is(err, storage.ErrOutOfOrderExemplar) {
+						outOfOrderExemplars++
+						// Only report out of order exemplars if all are out of order, otherwise this was a partial update
+						// to some existing set of exemplars.
+						if outOfOrderExemplars < len(ts.Exemplars) {
+							continue
+						}
+					}
+
 					// Error adding exemplar
 					updateFirstPartial(nil, func() softError {
 						return newTSDBIngestExemplarErr(err, model.Time(ex.TimestampMs), ts.Labels, ex.Labels)