func optimalPartSize(objectSize int64) (partSize int64, err error) {
	// object size is '-1' set it to 5TiB.
	if objectSize == -1 {
		objectSize = maxMultipartPutObjectSize
	}

	// object size is larger than supported maximum.
	if objectSize > maxMultipartPutObjectSize {
		err = errors.New("entity too large")
		return
	}

	configuredPartSize := minPartSize
	// Use floats for part size for all calculations to avoid

		// If separator is not found or is last entry, ok.
		return idx == -1 || idx == len(ext)-len(separator)
	}
	return false
}

// isLatestDeletemarker returns whether the latest version is a delete marker.
// If metadata is NOT versioned false will always be returned.
// If v2 and UNABLE to load metadata true will be returned.
func (e *metaCacheEntry) isLatestDeletemarker() bool {
	if e.cached != nil {

				t.Log("ListObjectVersions, bucket:", testCase.bucketName, "prefix:",
					testCase.prefix, "marker:", testCase.marker, "delimiter:",
					testCase.delimiter, "maxkeys:", testCase.maxKeys)

				resultV, err = obj.ListObjectVersions(context.Background(), testCase.bucketName,
					testCase.prefix, testCase.marker, "", testCase.delimiter, testCase.maxKeys)
			} else {

// Other important fields are Limit, Marker.
// List ID always derived from the Marker.
func (z *erasureServerPools) listPath(ctx context.Context, o *listPathOptions) (entries metaCacheEntriesSorted, err error) {
	if err := checkListObjsArgs(ctx, o.Bucket, o.Prefix, o.Marker); err != nil {
		return entries, err
	}

	// Marker points to before the prefix, just ignore it.
	if o.Marker < o.Prefix {
		o.Marker = ""
	}

	if err.HTTPStatusCode == http.StatusServiceUnavailable {
		// Set retry-after header to indicate user-agents to retry request after 120secs.
		// https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Retry-After
		w.Header().Set(xhttp.RetryAfter, "120")
	}

	switch err.Code {
	case "InvalidRegion":

		// If marker is *after* the last possible object from the prefix it should return an empty list.
		{
			bucketNames[0], "Asia", "europe-object", "", "", 0,
			ListMultipartsInfo{KeyMarker: "europe-object", Prefix: "Asia", IsTruncated: false},
			nil, true,
		},
		// Setting an invalid combination of uploadIDMarker and Marker (Test number 11-12).
		{

}

// GetDataDir returns an expected dataDir given FileInfo
//   - deleteMarker returns "delete-marker"
//   - returns "legacy" if FileInfo is XLV1 and DataDir is
//     empty, returns DataDir otherwise
//   - returns "dataDir"
func (fi FileInfo) GetDataDir() string {
	if fi.Deleted {
		return "delete-marker"
	}
	if fi.XLV1 && fi.DataDir == "" {
		return "legacy"
	}
	return fi.DataDir
}

	if gerr != nil { // error from GetObjectInfo
		if _, ok := gerr.(MethodNotAllowed); ok {
			// This happens usually for a delete marker
			if oi.DeleteMarker || !oi.VersionPurgeStatus.Empty() {
				// Delete marker should be present and valid.
				return nil
			}
		}
		if isErrObjectNotFound(gerr) || isErrVersionNotFound(gerr) {
			return nil
		}
		return gerr
	}

	// 3. If bucket versioning is enabled and
	//    a. version id is specified, remove its remote object.
	//    b. version id is not specified, nothing to be done (a delete marker is added).
	delTier := false
	switch {
	case !os.Versioned, os.Suspended: // 1, 2.a, 2.b
		delTier = true
	case os.Versioned && os.VersionID != "": // 3.a
		delTier = true
	}
	if delTier {

// Checks for all ListObjects arguments validity.
func checkListObjsArgs(ctx context.Context, bucket, prefix, marker string) error {
	// Verify if bucket is valid.
	if !isMinioMetaBucketName(bucket) && s3utils.CheckValidBucketNameStrict(bucket) != nil {
		return BucketNameInvalid{Bucket: bucket}
	}

	// Validates object prefix validity after bucket exists.
	if !IsValidObjectPrefix(prefix) {
		return ObjectNameInvalid{
			Bucket: bucket,