type allTierStats struct {
	Tiers map[string]tierStats `msg:"ts"`
}

func newAllTierStats() *allTierStats {
	return &allTierStats{
		Tiers: make(map[string]tierStats),
	}
}

func (ats *allTierStats) addSizes(tiers map[string]tierStats) {
	for tier, st := range tiers {
		ats.Tiers[tier] = ats.Tiers[tier].add(st)
	}
}

func (ats *allTierStats) merge(other *allTierStats) {
	for tier, st := range other.Tiers {

			// simply because getSize() function already heals the
			// object.
			delete(abandonedChildren, pathJoin(item.bucket, item.objectPath()))

			if err != errIgnoreFileContrib {
				into.addSizes(sz)
				into.Objects++
			}

			wait() // wait to proceed to next entry.

			return nil
		})
		if err != nil {
			return err
		}

		if foundObjects && globalIsErasure {

			Bytes: rt.SinceUptime.Bytes,
		},
		ErrCounts: errCounts,
	}
}

func (rt *RTimedMetrics) addsize(size int64, err error) {
	// failures seen since uptime
	atomic.AddInt64(&rt.SinceUptime.Bytes, size)
	atomic.AddInt64(&rt.SinceUptime.Count, 1)
	rt.LastMinute.addsize(size)
	rt.LastHour.addsize(size)
	if err != nil && minio.ToErrorResponse(err).Code == "AccessDenied" {
		if rt.ErrCounts == nil {

		bs.ReplicatedSize > 0 ||
		bs.ReplicaSize > 0
}

func (bs *BucketReplicationStat) updateXferRate(sz int64, duration time.Duration) {
	if sz > minLargeObjSize {
		bs.XferRateLrg.addSize(sz, duration)
	} else {
		bs.XferRateSml.addSize(sz, duration)
	}
}

// RMetricName - name of replication metric
type RMetricName string

const (
	// Large - objects larger than 128MiB
	Large RMetricName = "Large"

	mu        sync.Mutex
	init      sync.Once
	lastMinuteLatency
}

func (e *lockedLastMinuteLatency) add(value time.Duration) {
	e.addSize(value, 0)
}

// addSize will add a duration and size.
func (e *lockedLastMinuteLatency) addSize(value time.Duration, sz int64) {
	// alloc on every call, so we have a clean entry to swap in.
	t := time.Now().Unix()
	e.init.Do(func() {
		e.cached.Store(&AccElem{})

		b.ReplicatedCount++
		if rs.TransferDuration > 0 {
			b.Latency.update(rs.TransferSize, rs.TransferDuration)
			b.updateXferRate(rs.TransferSize, rs.TransferDuration)
		}
	case rs.Failed:
		b.FailStats.addsize(rs.TransferSize, rs.Err)
	case rs.Pending:
	}
}

type replStat struct {
	Arn       string
	Completed bool
	Pending   bool
	Failed    bool
	opType    replication.Type
	// transfer size

	startTime := time.Now()
	return func(sz int) {
		duration := time.Since(startTime)

		atomic.AddUint64(&p.operations[s], 1)
		if s < scannerMetricLastRealtime {
			p.latency[s].addSize(duration, int64(sz))
		}
	}
}

// incTime will increment time on metric s with a specific duration.
// Use for s < scannerMetricLastRealtime
func (p *scannerMetrics) incTime(s scannerMetric, d time.Duration) {

func calcAvg(x, y float64, n1, n2 int64) float64 {
	if n1+n2 == 0 {
		return 0
	}
	avg := (x*float64(n1) + y*float64(n2)) / float64(n1+n2)
	return avg
}

// Add a new transfer
func (rx *XferStats) addSize(sz int64, t time.Duration) {
	if rx.measure == nil {
		rx.measure = newRateMeasurement(time.Now())
	}
	rx.measure.incrementBytes(uint64(sz))
	rx.Curr = rx.measure.getExpMovingAvgBytesPerSecond()