loadNodesUpDown := func(ctx context.Context) (v nodesOnline, err error) {
		v.Online, v.Offline = globalNotificationSys.GetPeerOnlineCount()
		return
	}
	return cachevalue.NewFromFunc(1*time.Minute,
		cachevalue.Opts{ReturnLastGood: true},
		loadNodesUpDown)
}

type driveIOStatMetrics struct {
	readsPerSec    float64
	readsKBPerSec  float64
	readsAwait     float64
	writesPerSec   float64
	writesKBPerSec float64

)

// Opts contains options for the cache.
type Opts struct {
	// When set to true, return the last cached value
	// even if updating the value errors out.
	// Returns the last good value AND the error.
	ReturnLastGood bool

	// If NoWait is set, Get() will return the last good value,
	// if TTL has expired but 2x TTL has not yet passed,
	// but will fetch a new value in the background.
	NoWait bool
}

		return map[string]uint64{}, nil
	}

	cache := dataUsageCache{}

	prefixUsageCache.InitOnce(30*time.Second,
		// No need to fail upon Update() error, fallback to old value.
		cachevalue.Opts{ReturnLastGood: true, NoWait: true},
		func(ctx context.Context) (map[string]uint64, error) {
			m := make(map[string]uint64)
			for _, pool := range z.serverPools {
				for _, er := range pool.sets {
					// Load bucket usage prefixes

}

var bucketStorageCache = cachevalue.New[DataUsageInfo]()

// Init initialize bucket quota.
func (sys *BucketQuotaSys) Init(objAPI ObjectLayer) {
	bucketStorageCache.InitOnce(10*time.Second,
		cachevalue.Opts{ReturnLastGood: true, NoWait: true},
		func(ctx context.Context) (DataUsageInfo, error) {
			if objAPI == nil {
				return DataUsageInfo{}, errServerNotInitialized
			}
			ctx, done := context.WithTimeout(ctx, 2*time.Second)