type mrfState struct {
	opCh chan partialOperation
}

// Add a partial S3 operation (put/delete) when one or more disks are offline.
func (m *mrfState) addPartialOp(op partialOperation) {
	if m == nil {
		return
	}

	select {
	case m.opCh <- op:
	default:
	}
}

var healSleeper = newDynamicSleeper(5, time.Second, false)

// healRoutine listens to new disks reconnection events and

	tierPut
	tierDelete
)

func (op tierOp) String() string {
	switch op {
	case tierGet:
		return "GET"
	case tierPut:
		return "PUT"
	case tierDelete:
		return "DELETE"
	}
	return "UNKNOWN"
}

type tierPermErr struct {
	Op  tierOp
	Err error
}

func (te tierPermErr) Error() string {
	return fmt.Sprintf("failed to perform %s: %v", te.Op, te.Err)
}

	}
)

// logSuccess will update the last successful operation time.
func (h *healthDiskCtxValue) logSuccess() {
	atomic.StoreInt64(h.lastSuccess, time.Now().UnixNano())
}

// noopDoneFunc is a no-op done func.
// Can be reused.
var noopDoneFunc = func(_ *error) {}

// TrackDiskHealth for this request.
// When a non-nil error is returned 'done' MUST be called

		srcInfo.UserDefined[xhttp.AmzBucketReplicationStatus] = rs
	}

	op := replication.ObjectReplicationType
	if srcInfo.metadataOnly {
		op = replication.MetadataReplicationType
	}
	if dsc := mustReplicate(ctx, dstBucket, dstObject, srcInfo.getMustReplicateOptions(op, dstOpts)); dsc.ReplicateAny() {
		srcInfo.UserDefined[ReservedMetadataPrefixLower+ReplicationStatus] = dsc.PendingStatus()

		if len(logger.AuditTargets()) == 0 {
			return
		}

		op := auditTierOp{
			Tier:        tier,
			OutputBytes: bytes,
		}

		if err == nil {
			since := time.Since(startTime)
			op.TimeToResponseNS = since.Nanoseconds()
			globalTierMetrics.Observe(tier, since)
			globalTierMetrics.logSuccess(tier)
		} else {
			op.Error = err.Error()
			globalTierMetrics.logFailure(tier)
		}

	return os.Remove(oldLgFile)
}

func (w *Writer) rotate() error {
	if w.f != nil {
		if err := w.closeCurrentFile(); err != nil {
			return err
		}

		// This function is a no-op if opts.Compress is false
		// writes an error in JSON form to stderr, if we cannot
		// compress.
		if err := w.compress(); err != nil {

		if tgt.Empty() {
			writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErrWithErr(ErrRemoteTargetNotFoundError, err), r.URL)
			return
		}
		for _, op := range ops {
			switch op {
			case madmin.CredentialsUpdateType:
				if !globalSiteReplicationSys.isEnabled() {
					// credentials update is possible only in bucket replication. User will never
					// know the site replicator creds.

}

func (o ObjectInfo) getMustReplicateOptions(op replication.Type, opts ObjectOptions) mustReplicateOptions {
	return getMustReplicateOptions(o.UserDefined, o.UserTags, o.ReplicationStatus, op, opts)
}

func getMustReplicateOptions(userDefined map[string]string, userTags string, status replication.StatusType, op replication.Type, opts ObjectOptions) mustReplicateOptions {
	meta := cloneMSS(userDefined)

	// At this point, the local bucket is deleted.

	c.RLock()
	defer c.RUnlock()
	if !c.enabled {
		return nil
	}

	op := madmin.DeleteBucketBktOp
	if forceDelete {
		op = madmin.ForceDeleteBucketBktOp
	}

	// Send bucket delete to other clusters.
	cerr := c.concDo(nil, func(deploymentID string, p madmin.PeerInfo) error {

		return nil, time.Time{}, err
	}
	defer f.Close()
	stat, err := f.Stat()
	if err != nil {
		return nil, time.Time{}, err
	}
	if stat.IsDir() {
		return nil, time.Time{}, &os.PathError{
			Op:   "open",
			Path: itemPath,
			Err:  syscall.EISDIR,
		}
	}
	buf, err := readXLMetaNoData(f, stat.Size())
	if err != nil {
		return nil, stat.ModTime().UTC(), fmt.Errorf("%w -> %s", err, itemPath)
	}