histogram: prometheus.NewHistogramVec(prometheus.HistogramOpts{
		Name:    "tier_ttlb_seconds",
		Help:    "Time taken by requests served by warm tier",
		Buckets: []float64{0.01, 0.1, 1, 2, 5, 10, 60, 5 * 60, 15 * 60, 30 * 60},
	}, []string{"tier"}),
}

func (t *tierMetrics) Observe(tier string, dur time.Duration) {
	t.histogram.With(prometheus.Labels{"tier": tier}).Observe(dur.Seconds())
}

	os.TransitionTier = info.Tier
	os.TransitionStatus = info.Status
	os.RemoteObject = info.Name
	os.TransitionVersionID = info.VersionID
}

// shouldRemoveRemoteObject determines if a transitioned object should be
// removed from remote tier. If remote object is to be deleted, returns the
// corresponding tier deletion journal entry and true. Otherwise returns empty
// jentry value and false.

package cmd

import (
	"testing"
	"time"
)

func TestTierMetrics(t *testing.T) {
	tier := "WARM-1"
	globalTierMetrics.Observe(tier, 200*time.Millisecond)
	expSuccess := 10
	expFailure := 5
	for i := 0; i < expSuccess; i++ {
		globalTierMetrics.logSuccess(tier)
	}
	for i := 0; i < expFailure; i++ {
		globalTierMetrics.logFailure(tier)
	}
	metrics := globalTierMetrics.Report()
	var succ, fail float64

				err = msgp.WrapError(err, "ObjName")
				return
			}
		case "vid":
			z.VersionID, err = dc.ReadString()
			if err != nil {
				err = msgp.WrapError(err, "VersionID")
				return
			}
		case "tier":
			z.TierName, err = dc.ReadString()
			if err != nil {
				err = msgp.WrapError(err, "TierName")
				return
			}
		default:
			err = dc.Skip()
			if err != nil {
				err = msgp.WrapError(err)
				return

		}
	}
}

func (j *tierMemJournal) AddEntry(je jentry) error {
	select {
	case j.entries <- je:
	default:
		return fmt.Errorf("failed to remove tiered content at %s with version %s from tier %s, will be retried later.",
			je.ObjName, je.VersionID, je.TierName)
	}
	return nil

	for tier, st := range other.Tiers {
		ats.Tiers[tier] = ats.Tiers[tier].add(st)
	}
}

func (ats *allTierStats) clone() *allTierStats {
	if ats == nil {
		return nil
	}
	dst := *ats
	dst.Tiers = make(map[string]tierStats, len(ats.Tiers))
	for tier, st := range ats.Tiers {
		dst.Tiers[tier] = st
	}
	return &dst
}

		cacheDuration = defaultCacheDuration
	}
	timer := time.NewTimer(cacheDuration)
	defer timer.Stop()

	for {
		select {
		case <-ctx.Done():
			return
		case <-timer.C:
			c.RefreshKey(ctx, logger)

			// Reset for the next interval
			timer.Reset(cacheDuration)
		}
	}
}

type kesClient struct {
	lock         sync.RWMutex

			wg.Wait()

			// Reset for the next interval
			timer.Reset(globalAPIConfig.getDeleteCleanupInterval())
		}
	}
}

func (s *erasureSets) cleanupStaleUploads(ctx context.Context) {
	timer := time.NewTimer(globalAPIConfig.getStaleUploadsCleanupInterval())
	defer timer.Stop()

	for {
		select {
		case <-ctx.Done():
			return
		case <-timer.C:
			var wg sync.WaitGroup
			for _, set := range s.sets {

	fivs, err := getAllFileInfoVersions(xlMetaBuf, volume, path, allParts)
	if err != nil {
		return fivs, err
	}
	n := 0
	for _, fi := range fivs.Versions {
		// Filter our tier object delete marker
		if !fi.TierFreeVersion() {
			fivs.Versions[n] = fi
			n++
		} else {
			fivs.FreeVersions = append(fivs.FreeVersions, fi)
		}
	}
	fivs.Versions = fivs.Versions[:n]
	// Update numversions

			if err != nil {
				return nil
			}
			w := xioutil.NewDeadlineWorker(globalDriveConfig.GetMaxTimeout())
			return w.Run(func() error {
				wait := deleteMultipartCleanupSleeper.Timer(ctx)
				if time.Since(fi.ModTime) > expiry {
					pathUUID := mustGetUUID()
					targetPath := pathJoin(drivePath, minioMetaTmpDeletedBucket, pathUUID)