r = objLayer.Health(GlobalContext, HealthOptions{})
		return r, err
	}
	return cachevalue.NewFromFunc(1*time.Minute,
		cachevalue.Opts{ReturnLastGood: true},
		loadHealth,
	)
}

func getDiffStats(initialStats, currentStats madmin.DiskIOStats) madmin.DiskIOStats {
	return madmin.DiskIOStats{
		ReadIOs:      currentStats.ReadIOs - initialStats.ReadIOs,
		WriteIOs:     currentStats.WriteIOs - initialStats.WriteIOs,

	sectorSize := uint64(512)
	kib := float64(1 << 10)
	diffInSeconds := time.Now().UTC().Sub(lastDriveStatsRefresh).Seconds()
	if diffInSeconds == 0 {
		// too soon to update the stats
		return
	}
	diffStats := getDiffStats(latestStats, currentStats)

	updateResourceMetrics(driveSubsystem, readsPerSec, float64(diffStats.ReadIOs)/diffInSeconds, labels, false)
	readKib := float64(diffStats.ReadSectors*sectorSize) / kib