MQE: Handle min/max NaN's same as promql (#9212)

* MQE: Handle min/max NaN's same as promql

* Update CHANGELOG

* Add comment

Author: jhesketh

CHANGELOG.md

@@ -32,7 +32,7 @@
 * [CHANGE] Querier: allow wrapping errors with context errors only when the former actually correspond to `context.Canceled` and `context.DeadlineExceeded`. #9175
 * [FEATURE] Alertmanager: Added `-alertmanager.log-parsing-label-matchers` to control logging when parsing label matchers. This flag is intended to be used with `-alertmanager.utf8-strict-mode-enabled` to validate UTF-8 strict mode is working as intended. The default value is `false`. #9173
 * [FEATURE] Alertmanager: Added `-alertmanager.utf8-migration-logging-enabled` to enable logging of tenant configurations that are incompatible with UTF-8 strict mode. The default value is `false`. #9174
-* [FEATURE] Querier: add experimental streaming PromQL engine, enabled with `-querier.query-engine=mimir`. #8422 #8430 #8454 #8455 #8360 #8490 #8508 #8577 #8660 #8671 #8677 #8747 #8850 #8872 #8838 #8911 #8909 #8923 #8924 #8925 #8932 #8933 #8934 #8962 #8986 #8993 #8995 #9008 #9017 #9018 #9019 #9120 #9121 #9136 #9139 #9140 #9145 #9191 #9194 #9196
+* [FEATURE] Querier: add experimental streaming PromQL engine, enabled with `-querier.query-engine=mimir`. #8422 #8430 #8454 #8455 #8360 #8490 #8508 #8577 #8660 #8671 #8677 #8747 #8850 #8872 #8838 #8911 #8909 #8923 #8924 #8925 #8932 #8933 #8934 #8962 #8986 #8993 #8995 #9008 #9017 #9018 #9019 #9120 #9121 #9136 #9139 #9140 #9145 #9191 #9194 #9196 #9212
 * [FEATURE] Experimental Kafka-based ingest storage. #6888 #6894 #6929 #6940 #6951 #6974 #6982 #7029 #7030 #7091 #7142 #7147 #7148 #7153 #7160 #7193 #7349 #7376 #7388 #7391 #7393 #7394 #7402 #7404 #7423 #7424 #7437 #7486 #7503 #7508 #7540 #7621 #7682 #7685 #7694 #7695 #7696 #7697 #7701 #7733 #7734 #7741 #7752 #7838 #7851 #7871 #7877 #7880 #7882 #7887 #7891 #7925 #7955 #7967 #8031 #8063 #8077 #8088 #8135 #8176 #8184 #8194 #8216 #8217 #8222 #8233 #8503 #8542 #8579 #8657 #8686 #8688 #8703 #8706 #8708 #8738 #8750 #8778 #8808 #8809 #8841 #8842 #8845 #8853 #8886 #8988
   * What it is:
     * When the new ingest storage architecture is enabled, distributors write incoming write requests to a Kafka-compatible backend, and the ingesters asynchronously replay ingested data from Kafka. In this architecture, the write and read path are de-coupled through a Kafka-compatible backend. The write path and Kafka load is a function of the incoming write traffic, the read path load is a function of received queries. Whatever the load on the read path, it doesn't affect the write path.

pkg/streamingpromql/aggregations/min_max.go

@@ -34,14 +34,16 @@ func NewMinMaxAggregationGroup(max bool) *MinMaxAggregationGroup {
 }
 
 func (g *MinMaxAggregationGroup) maxAccumulatePoint(idx int64, f float64) {
-	if !g.floatPresent[idx] || g.floatPresent[idx] && f > g.floatValues[idx] {
+	// We return a NaN only if there are no other values to return
+	if !g.floatPresent[idx] || f > g.floatValues[idx] || math.IsNaN(g.floatValues[idx]) {
 		g.floatValues[idx] = f
 		g.floatPresent[idx] = true
 	}
 }
 
 func (g *MinMaxAggregationGroup) minAccumulatePoint(idx int64, f float64) {
-	if !g.floatPresent[idx] || g.floatPresent[idx] && f < g.floatValues[idx] {
+	// We return a NaN only if there are no other values to return
+	if !g.floatPresent[idx] || f < g.floatValues[idx] || math.IsNaN(g.floatValues[idx]) {
 		g.floatValues[idx] = f
 		g.floatPresent[idx] = true
 	}
@@ -68,9 +70,6 @@ func (g *MinMaxAggregationGroup) AccumulateSeries(data types.InstantVectorSeries
 	}
 
 	for _, p := range data.Floats {
-		if math.IsNaN(p.F) {
-			continue
-		}
 		idx := (p.T - start) / interval
 		g.accumulatePoint(idx, p.F)
 	}

pkg/streamingpromql/testdata/ours/aggregators.test

@@ -191,6 +191,27 @@ eval range from 0 to 2m step 1m min(histogram_only_series)
 
 clear
 
+# Test min/max with NaN
+load 1m
+	mixed_series{type="float", label="value"}   NaN
+	mixed_series{type="float", label="value2"}  -5
+	mixed_series{type="float", label="value3"}  10
+	mixed_series{type="histogram", label="value"}   {{schema:1 sum:5 count:5 buckets:[1 3 1]}}
+	mixed_series{type="histogram", label="value2"}  NaN
+  mixed_series{type="onlyNaN"} NaN
+
+eval instant at 1m min by (type) (mixed_series)
+	{type="float"} -5
+	{type="histogram"} 0
+  {type="onlyNaN"} NaN
+
+eval instant at 1m max by (type) (mixed_series)
+	{type="float"} 10
+	{type="histogram"} 0
+  {type="onlyNaN"} NaN
+
+clear
+
 # Test native histogram compaction
 load 1m
     single_histogram{label="value"}  {{schema:1 sum:5 count:5 buckets:[1 3 1 4 0 2]}}