var errUnsupportedJournalVersion = errors.New("unsupported pending deletes journal version")

func newTierDiskJournal() *tierDiskJournal {
	return &tierDiskJournal{}
}

// NewTierJournal initializes tier deletion journal
func NewTierJournal() *TierJournal {
	j := &TierJournal{
		tierMemJournal:  newTierMemJournal(1000),
		tierDiskJournal: newTierDiskJournal(),
	}
	return j
}

// Init initializes an in-memory journal built using a