func()

in v1storage/storage.go [1369:1418]

• 43 lines of code
• 11 McCabe index (conditional complexity)

func (s *MemorySeriesStorage) cycleThroughMemoryFingerprints() chan model.Fingerprint {
	memoryFingerprints := make(chan model.Fingerprint)
	go func() {
		defer close(memoryFingerprints)
		firstPass := true

		for {
			// Initial wait, also important if there are no FPs yet.
			if !s.waitForNextFP(s.fpToSeries.length(), 1) {
				return
			}
			begin := time.Now()
			fps := s.fpToSeries.sortedFPs()
			if firstPass && len(fps) > 0 {
				// Start first pass at a random location in the
				// key space to cover the whole key space even
				// in the case of frequent restarts.
				fps = fps[rand.Intn(len(fps)):]
			}
			count := 0
			for _, fp := range fps {
				select {
				case memoryFingerprints <- fp:
				case <-s.loopStopping:
					return
				}
				// Reduce the wait time according to the urgency score.
				score, rushed := s.getPersistenceUrgencyScore()
				if rushed {
					score = 1
				}
				s.waitForNextFP(s.fpToSeries.length(), 1-score)
				count++
			}
			if count > 0 {
				msg := "full"
				if firstPass {
					msg = "initial partial"
				}
				log.Infof(
					"Completed %s maintenance sweep through %d in-memory fingerprints in %v.",
					msg, count, time.Since(begin),
				)
			}
			firstPass = false
		}
	}()

	return memoryFingerprints
}