manager/dedup.go
func (d *DedupManager) Stop() error {
	d.stopLock.Lock()
	defer d.stopLock.Unlock()
	if d.stop {
		return nil
	}

	log.Printf("[INFO] (dedup) stopping de-duplication manager")
	d.stop = true
	close(d.stopCh)
	d.wg.Wait()
	return nil
}
func (d *DedupManager) Stop() error {
	d.stopLock.Lock()
	defer d.stopLock.Unlock()
	if d.stop {
		return nil
	}

	log.Printf("[INFO] (dedup) stopping de-duplication manager")
	d.stop = true
	close(d.stopCh)
	d.wg.Wait()
	return nil
}
// Stop is used to stop the de-duplication manager