Method backFillLimit

pkg/ingester/user_state.go:133–161

(ctx context.Context, u *userTSDB, forceBackfill bool, allLimits []validation.LimitsPerLabelSet, limit validation.LimitsPerLabelSet, s *labelSetCounterShard)

}

func (m *labelSetCounter) backFillLimit(ctx context.Context, u *userTSDB, forceBackfill bool, allLimits []validation.LimitsPerLabelSet, limit validation.LimitsPerLabelSet, s *labelSetCounterShard) (int, error) {
	s.Lock()
	defer s.Unlock()
	// If not force backfill, use existing counter value.
	if !forceBackfill {
		if r, ok := s.valuesCounter[limit.Hash]; ok {
			return r.count, nil
		}
	}

	ir, err := u.db.Head().Index()
	if err != nil {
		return 0, err
	}

	defer ir.Close()

	numSeries := u.db.Head().NumSeries()
	totalCount, err := getCardinalityForLimitsPerLabelSet(ctx, numSeries, ir, allLimits, limit)
	if err != nil {
		return 0, err
	}

	s.valuesCounter[limit.Hash] = &labelSetCounterEntry{
		count:  totalCount,
		labels: limit.LabelSet,
	}
	return totalCount, nil
}

func getCardinalityForLimitsPerLabelSet(ctx context.Context, numSeries uint64, ir tsdb.IndexReader, allLimits []validation.LimitsPerLabelSet, limit validation.LimitsPerLabelSet) (int, error) {
	// Easy path with explicit labels.