driveOfflineCount = "offline_count"
	driveOnlineCount  = "online_count"
	driveCount        = "count"

	// iostat related
	driveReadsPerSec    = "reads_per_sec"
	driveReadsKBPerSec  = "reads_kb_per_sec"
	driveReadsAwait     = "reads_await"
	driveWritesPerSec   = "writes_per_sec"
	driveWritesKBPerSec = "writes_kb_per_sec"
	driveWritesAwait    = "writes_await"
	drivePercUtil       = "perc_util"
)

var (

	// drive stats
	totalInodes    MetricName = "total_inodes"
	readsPerSec    MetricName = "reads_per_sec"
	writesPerSec   MetricName = "writes_per_sec"
	readsKBPerSec  MetricName = "reads_kb_per_sec"
	writesKBPerSec MetricName = "writes_kb_per_sec"
	readsAwait     MetricName = "reads_await"
	writesAwait    MetricName = "writes_await"
	percUtil       MetricName = "perc_util"
	usedInodes     MetricName = "used_inodes"

| `minio_system_drive_reads_per_sec`             | `gauge`   | Reads per second on a drive                                        | `drive,set_index,drive_index,pool_index,server`     |
| `minio_system_drive_reads_kb_per_sec`          | `gauge`   | Kilobytes read per second on a drive                               | `drive,set_index,drive_index,pool_index,server`     |

| `minio_node_drive_used_inodes`       | Total inodes used on a drive.                            |
| `minio_node_drive_reads_per_sec`     | Reads per second on a drive.                             |
| `minio_node_drive_reads_kb_per_sec`  | Kilobytes read per second on a drive.                    |
| `minio_node_drive_reads_await`       | Average time for read requests to be served on a drive.  |