// `api` label values.
func getHistogramMetrics(hist *prometheus.HistogramVec, desc MetricDescription, toLowerAPILabels bool) []MetricV2 {
	ch := make(chan prometheus.Metric)
	go func() {
		defer xioutil.SafeClose(ch)
		// Collects prometheus metrics from hist and sends it over ch
		hist.Collect(ch)
	}()

	// Converts metrics received into internal []Metric type

	// this option is set when active-active replication is in place between site A -> B,
	// and request hits site B that does not have the object yet.
	if opts.ProxyRequest || (opts.ProxyHeaderSet && !opts.ProxyRequest) { // true only when site B sets MinIOSourceProxyRequest header
		return proxy
	}
	var wg sync.WaitGroup

	}
	return
}

// EncodeMsg implements msgp.Encodable
func (z *xlMetaDataDirDecoder) EncodeMsg(en *msgp.Writer) (err error) {
	// check for omitted fields
	zb0001Len := uint32(1)
	var zb0001Mask uint8 /* 1 bits */
	_ = zb0001Mask
	if z.ObjectV2 == nil {
		zb0001Len--
		zb0001Mask |= 0x1
	}
	// variable map header, size zb0001Len
	err = en.Append(0x80 | uint8(zb0001Len))
	if err != nil {
		return
	}

	// MD5 checksum.
	ErrMissingCustomerKeyMD5 = Errorf("The SSE-C request is missing the customer key MD5")

	// ErrInvalidCustomerKey indicates that the SSE-C client key is not valid - e.g. not a
	// base64-encoded string or not 256 bits long.
	ErrInvalidCustomerKey = Errorf("The SSE-C client key is invalid")

	// ErrSecretKeyMismatch indicates that the provided secret key (SSE-C client key / SSE-S3 KMS key)

	return
}

// EncodeMsg implements msgp.Encodable
func (z *dataUsageEntry) EncodeMsg(en *msgp.Writer) (err error) {
	// check for omitted fields
	zb0001Len := uint32(10)
	var zb0001Mask uint16 /* 10 bits */
	_ = zb0001Mask
	if z.ReplicationStats == nil {
		zb0001Len--
		zb0001Mask |= 0x80
	}
	if z.AllTierStats == nil {
		zb0001Len--
		zb0001Mask |= 0x100
	}

)

const letterBytes = "abcdefghijklmnopqrstuvwxyz01234569"
const (
	letterIdxBits = 6                    // 6 bits to represent a letter index
	letterIdxMask = 1<<letterIdxBits - 1 // All 1-bits, as many as letterIdxBits
	letterIdxMax  = 63 / letterIdxBits   // # of letter indices fitting in 63 bits
)

// Random number state.
// We generate random temporary file names so that there's a good

	peerPrefix      = "peer"
	peerPrefixS3    = "peerS3"
	healPrefix      = "heal"
)

func init() {
	// Static check if we exceed 255 handler ids.
	// Extend the type to uint16 when hit.
	if handlerLast > 255 {
		panic(fmt.Sprintf("out of handler IDs. %d > %d", handlerLast, 255))
	}
}

func (h HandlerID) valid() bool {
	return h != handlerInvalid && h < handlerLast
}

	cpuLoad15Perc MetricName = "load15_perc"
)

var (
	resourceCollector *minioResourceCollector
	// resourceMetricsMap is a map of subsystem to its metrics
	resourceMetricsMap   map[MetricSubsystem]ResourceMetrics
	resourceMetricsMapMu sync.RWMutex
	// resourceMetricsHelpMap maps metric name to its help string
	resourceMetricsHelpMap map[MetricName]string
	resourceMetricsGroups  []*MetricsGroupV2

	}
	info.Used = info.Total - info.Free
	return info, nil
}

// GetDriveStats returns IO stats of the drive by its major:minor
func GetDriveStats(major, minor uint32) (iostats IOStats, err error) {
	return IOStats{}, errors.New("operation unsupported")

		apiErr := errorCodes.ToAPIErr(ErrInvalidCopyPartRangeSource)
		apiErr.Description = err.Error()
		writeErrorResponse(ctx, w, apiErr, url)
		return
	}
}

// Parses x-amz-copy-source-range for CopyObjectPart API. Its behavior
// is different from regular HTTP range header. It only supports the
// form `bytes=first-last` where first and last are zero-based byte
// offsets. See