err = msgp.WrapError(err, "Namespace")
					return
				}
				z.Namespace = MetricNamespace(zb0002)
			}
		case "Subsystem":
			{
				var zb0003 string
				zb0003, bts, err = msgp.ReadStringBytes(bts)
				if err != nil {
					err = msgp.WrapError(err, "Subsystem")
					return
				}
				z.Subsystem = MetricSubsystem(zb0003)
			}
		case "Name":
			{
				var zb0004 string

//
// `key` can be one of three forms:
// 1. `subsys:target` -> request for config of a single subsystem and target pair.
// 2. `subsys:` -> request for config of a single subsystem and the default target.
// 3. `subsys` -> request for config of all targets for the given subsystem.
//
// This is a reporting API and config secrets are redacted in the response.

		Namespace: nodeMetricNamespace,
		Subsystem: tierSubsystem,
		Name:      ttlbDistribution,
		Help:      "Distribution of time to last byte for objects downloaded from warm tier",
		Type:      gaugeMetric,
	}

	// {minio_node}_{tier}_{requests_success}
	tierRequestsSuccessMD = MetricDescription{
		Namespace: nodeMetricNamespace,
		Subsystem: tierSubsystem,
		Name:      tierRequestsSuccess,

		Namespace: nodeMetricNamespace,
		Subsystem: subSys,
		Name:      name,
		Help:      help,
		Type:      gaugeMetric,
	}
}

func getResourceMetrics() *MetricsGroupV2 {
	mg := &MetricsGroupV2{
		cacheInterval: resourceMetricsCacheInterval,
	}
	mg.RegisterRead(func(ctx context.Context) []MetricV2 {
		metrics := []MetricV2{}

// target are valid. It checks both the configuration store as well as
// environment variables.
func (c Config) CheckValidKeys(subSys string, deprecatedKeys []string) error {
	defKVS, ok := DefaultKVS[subSys]
	if !ok {
		return Errorf("Subsystem %s does not exist", subSys)
	}

	// Make a list of valid keys for the subsystem including the `comment`
	// key.

	var l string
	if anonFlag {
		l = reflect.TypeOf(err).String()
	} else {
		l = fmt.Sprintf("%v (%T)", err, err)
	}
	return buildLogEntry(ctx, subsystem, l, getTrace(3), errKind...)
}

func logToEntry(ctx context.Context, subsystem, message string, errKind ...interface{}) log.Entry {
	return buildLogEntry(ctx, subsystem, message, nil, errKind...)

// to refresh remote targets from bucket metadata.
type arnErrs struct {
	count            int64
	updateInProgress bool
	bucket           string
}

// BucketTargetSys represents bucket targets subsystem
type BucketTargetSys struct {
	sync.RWMutex
	arnRemotesMap map[string]arnTarget
	targetsMap    map[string][]madmin.BucketTarget
	hMutex        sync.RWMutex
	hc            map[string]epHealth

```

### API

By default, there is no limitation on the number of concurrent requests that a server/cluster processes at the same time. However, it is possible to impose such limitation using the API subsystem. Read more about throttling limitation in MinIO server [here](https://github.com/minio/minio/blob/master/docs/throttle/README.md).

```
KEY:

	globalLifecycleSys = NewLifecycleSys()

	// Create new bucket encryption subsystem
	globalBucketSSEConfigSys = NewBucketSSEConfigSys()

	// Create new bucket object lock subsystem
	globalBucketObjectLockSys = NewBucketObjectLockSys()

	// Create new bucket quota subsystem
	globalBucketQuotaSys = NewBucketQuotaSys()

	// Create new bucket versioning subsystem
	if globalBucketVersioningSys == nil {

	TransitionedVersionID = "transitioned-versionID"
	// TransitionTier name of transition storage class
	TransitionTier = "transition-tier"
)

// LifecycleSys - Bucket lifecycle subsystem.
type LifecycleSys struct{}

// Get - gets lifecycle config associated to a given bucket name.
func (sys *LifecycleSys) Get(bucketName string) (lc *lifecycle.Lifecycle, err error) {