<pre>
const (
	c1 = imag(2i)                    // imag(2i) = 2.0 is a constant
	c2 = len([10]float64{2})         // [10]float64{2} contains no function calls
	c3 = len([10]float64{c1})        // [10]float64{c1} contains no function calls
	c4 = len([10]float64{imag(2i)})  // imag(2i) is a constant and no function call is issued
	c5 = len([10]float64{imag(z)})   // invalid: imag(z) is a (non-constant) function call
)
var z complex128
</pre>

<pre>
const (
	c1 = imag(2i)                    // imag(2i) = 2.0 is a constant
	c2 = len([10]float64{2})         // [10]float64{2} contains no function calls
	c3 = len([10]float64{c1})        // [10]float64{c1} contains no function calls
	c4 = len([10]float64{imag(2i)})  // imag(2i) is a constant and no function call is issued
	c5 = len([10]float64{imag(z)})   // invalid: imag(z) is a (non-constant) function call
)
var z complex128
</pre>

			r.opts.HeaderSize = 0
			need = int(math.Min(float64(b-hdr), float64(need))) // use remaining tokens towards payload
			tokens = need + hdr

		} else { // part of header can be accommodated
			r.opts.HeaderSize -= b - 1
			need = 1 // to ensure we read at least one byte for every Read
			tokens = b
		}
	} else { // all tokens go towards payload
		need = int(math.Min(float64(b), float64(need)))
		tokens = need
	}

	}
	if count > 0 {
		lrg := XferStats{
			Avg:  lavg / float64(count),
			Curr: lcurr / float64(count),
			Peak: lpeak,
		}
		sml := XferStats{
			Avg:  savg / float64(count),
			Curr: scurr / float64(count),
			Peak: speak,
		}
		qs.XferStats[Large] = lrg
		qs.XferStats[Small] = sml
		qs.XferStats[Total] = XferStats{
			Avg:  (savg + lavg) / float64(count),
			Curr: (lcurr + scurr) / float64(count),

			Buckets: []float64{.05, .1, .25, .5, 1, 2.5, 5, 10},
		},
		[]string{"api"},
	)
	bucketHTTPRequestsDuration = prometheus.NewHistogramVec(
		prometheus.HistogramOpts{
			Name:    "s3_ttfb_seconds",
			Help:    "Time taken by requests served by current MinIO server instance per bucket",
			Buckets: []float64{.05, .1, .25, .5, 1, 2.5, 5, 10},
		},
		[]string{"api", "bucket"},
	)

					m.Set(bucketReplProxiedHeadRequestsTotal, float64(s.ProxyStats.HeadTotal), labels...)
					m.Set(bucketReplProxiedPutTaggingRequestsFailures, float64(s.ProxyStats.PutTagFailedTotal), labels...)
					m.Set(bucketReplProxiedPutTaggingRequestsTotal, float64(s.ProxyStats.PutTagTotal), labels...)
					m.Set(bucketReplSentCount, float64(stat.ReplicatedCount), labels...)

		if globalExpiryState != nil {
			expPendingTasks.Value = float64(globalExpiryState.PendingTasks())
			expMissedTasks.Value = float64(globalExpiryState.stats.MissedTasks())
			expMissedFreeVersions.Value = float64(globalExpiryState.stats.MissedFreeVersTasks())
			expMissedTierJournalTasks.Value = float64(globalExpiryState.stats.MissedTierJournalTasks())
			expNumWorkers.Value = float64(globalExpiryState.stats.NumWorkers())
		}

		Peak:    peak,
		Curr:    curr,
		measure: rx.measure,
		N:       rx.N + o.N,
	}
}

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 {

	Labels map[string]string

	// value captured in current cycle
	Current float64

	// Used when system provides cumulative (since uptime) values
	// helps in calculating the current value by comparing the new
	// cumulative value with previous one
	Cumulative float64

	Max   float64
	Avg   float64
	Sum   float64
	Count uint64
}

func init() {

	m.Set(usageTotalBytes, float64(clusterSize))
	m.Set(usageObjectsCount, float64(clusterObjectsCount))
	m.Set(usageVersionsCount, float64(clusterVersionsCount))
	m.Set(usageDeleteMarkersCount, float64(clusterDeleteMarkersCount))
	m.Set(usageBucketsCount, float64(clusterBuckets))
	for k, v := range clusterObjectSizesHistogram {
		m.Set(usageSizeDistribution, float64(v), "range", k)
	}