lib/storage: fix TestUpdateCurrHourMetricIDs test when it runs on the first hour of the day by UTC

lib/storage/storage.go

@@ -2496,7 +2496,7 @@ func (s *Storage) updateNextDayMetricIDs(date uint64) {
 	if e.date == date {
 		pendingMetricIDs.Union(&e.v)
 	} else {
-		// Do not add pendingMetricIDs from the previous day to the cyrrent day,
+		// Do not add pendingMetricIDs from the previous day to the current day,
 		// since this may result in missing registration of the metricIDs in the per-day inverted index.
 		// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3309
 		pendingMetricIDs = &uint64set.Set{}
@@ -2535,9 +2535,8 @@ func (s *Storage) updateCurrHourMetricIDs(hour uint64) {
 		byTenant = make(map[accountProjectKey]*uint64set.Set)
 		isFull = true
 	}
-
-	if hour%24 != 0 {
-		// Do not add pending metricIDs from the previous hour to the current hour on the next day,
+	if hm.hour == hour || hour%24 != 0 {
+		// Do not add pending metricIDs from the previous hour on the previous day to the current hour,
 		// since this may result in missing registration of the metricIDs in the per-day inverted index.
 		// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3309
 		for _, x := range newEntries {

lib/storage/storage_test.go

@@ -156,9 +156,12 @@ func TestUpdateCurrHourMetricIDs(t *testing.T) {
 	t.Run("empty_pending_metric_ids_stale_curr_hour", func(t *testing.T) {
 		s := newStorage()
 		hour := fasttime.UnixHour()
+		if hour%24 == 0 {
+			hour++
+		}
 		hmOrig := &hourMetricIDs{
 			m:    &uint64set.Set{},
-			hour: 123,
+			hour: hour - 1,
 		}
 		hmOrig.m.Add(12)
 		hmOrig.m.Add(34)
@@ -251,9 +254,12 @@ func TestUpdateCurrHourMetricIDs(t *testing.T) {
 		}
 
 		hour := fasttime.UnixHour()
+		if hour%24 == 0 {
+			hour++
+		}
 		hmOrig := &hourMetricIDs{
 			m:    &uint64set.Set{},
-			hour: 123,
+			hour: hour - 1,
 		}
 		hmOrig.m.Add(12)
 		hmOrig.m.Add(34)
@@ -355,6 +361,74 @@ func TestUpdateCurrHourMetricIDs(t *testing.T) {
 			t.Fatalf("unexpected s.pendingHourEntries.Len(); got %d; want %d", len(s.pendingHourEntries), 0)
 		}
 	})
+	t.Run("nonempty_pending_metric_ids_valid_curr_hour_start_of_day", func(t *testing.T) {
+		s := newStorage()
+		s.pendingHourEntries = []pendingHourMetricIDEntry{
+			{AccountID: 123, ProjectID: 431, MetricID: 343},
+			{AccountID: 123, ProjectID: 431, MetricID: 32424},
+			{AccountID: 1, ProjectID: 2, MetricID: 8293432},
+		}
+		mExpected := &uint64set.Set{}
+		for _, e := range s.pendingHourEntries {
+			mExpected.Add(e.MetricID)
+		}
+		byTenantExpected := make(map[accountProjectKey]*uint64set.Set)
+		for _, e := range s.pendingHourEntries {
+			k := accountProjectKey{
+				AccountID: e.AccountID,
+				ProjectID: e.ProjectID,
+			}
+			x := byTenantExpected[k]
+			if x == nil {
+				x = &uint64set.Set{}
+				byTenantExpected[k] = x
+			}
+			x.Add(e.MetricID)
+		}
+
+		hour := fasttime.UnixHour()
+		hour -= hour % 24
+		hmOrig := &hourMetricIDs{
+			m:    &uint64set.Set{},
+			hour: hour,
+		}
+		hmOrig.m.Add(12)
+		hmOrig.m.Add(34)
+		s.currHourMetricIDs.Store(hmOrig)
+		s.updateCurrHourMetricIDs(hour)
+		hmCurr := s.currHourMetricIDs.Load().(*hourMetricIDs)
+		if hmCurr.hour != hour {
+			// It is possible new hour occurred. Update the hour and verify it again.
+			hour = uint64(timestampFromTime(time.Now())) / msecPerHour
+			if hmCurr.hour != hour {
+				t.Fatalf("unexpected hmCurr.hour; got %d; want %d", hmCurr.hour, hour)
+			}
+			// Do not run other checks, since they may fail.
+			return
+		}
+		m := mExpected.Clone()
+		hmOrig.m.ForEach(func(part []uint64) bool {
+			for _, metricID := range part {
+				m.Add(metricID)
+			}
+			return true
+		})
+		if !hmCurr.m.Equal(m) {
+			t.Fatalf("unexpected hm.m; got %v; want %v", hmCurr.m, m)
+		}
+		if !reflect.DeepEqual(hmCurr.byTenant, byTenantExpected) {
+			t.Fatalf("unexpected hmPrev.byTenant; got %v; want %v", hmCurr.byTenant, byTenantExpected)
+		}
+
+		hmPrev := s.prevHourMetricIDs.Load().(*hourMetricIDs)
+		hmEmpty := &hourMetricIDs{}
+		if !reflect.DeepEqual(hmPrev, hmEmpty) {
+			t.Fatalf("unexpected hmPrev; got %v; want %v", hmPrev, hmEmpty)
+		}
+		if len(s.pendingHourEntries) != 0 {
+			t.Fatalf("unexpected s.pendingHourEntries.Len(); got %d; want %d", len(s.pendingHourEntries), 0)
+		}
+	})
 	t.Run("nonempty_pending_metric_ids_from_previous_hour_new_day", func(t *testing.T) {
 		s := newStorage()