}

func (m *MetricValues) setDriveBasicMetrics(drive madmin.Disk, labels []string) {
	m.Set(driveUsedBytes, float64(drive.UsedSpace), labels...)
	m.Set(driveFreeBytes, float64(drive.AvailableSpace), labels...)
	m.Set(driveTotalBytes, float64(drive.TotalSpace), labels...)
	m.Set(driveUsedInodes, float64(drive.UsedInodes), labels...)
	m.Set(driveFreeInodes, float64(drive.FreeInodes), labels...)

drives.  Therefore, the number of drives you present must be a multiple of one of these numbers.  Each object is written to a single erasure-coding set.

Minio uses the largest possible EC set size which divides into the number of drives given. For example, *18 drives* are configured as *2 sets of 9 drives*, and *24 drives* are configured as *2 sets of 12 drives*.  This is true for scenarios when running MinIO as a standalone erasure coded deployment. In [distributed setup however node (affinity)...

		readsPerSec:       "Reads per second on a drive",
		writesPerSec:      "Writes per second on a drive",
		readsKBPerSec:     "Kilobytes read per second on a drive",
		writesKBPerSec:    "Kilobytes written per second on a drive",
		readsAwait:        "Average time for read requests to be served on a drive",
		writesAwait:       "Average time for write requests to be served on a drive",

| `minio_system_drive_used_inodes`               | Total used inodes on a drive. <br><br>Type: gauge                                       | `drive`, `set_index`, `drive_index`, `pool_index`, `server`        |

          "legendFormat": "Free [{{drive}}]",
          "refId": "C"
        }
      ],
      "title": "Drive Usage",
      "type": "timeseries"
    },
    {
      "datasource": {
        "type": "prometheus",
        "uid": "${DS_PROMETHEUS}"
      },
      "description": "",
      "fieldConfig": {
        "defaults": {
          "color": {
            "mode": "palette-classic"
          },

| `minio_node_drive_total_inodes`      | Total inodes on a drive.                                 |
| `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.                    |

two parity drives, 100 MiB file takes only approximately 114 MiB.

Below is a list of data/parity drives and corresponding _approximate_ storage space usage on a 16 drive MinIO deployment. The field _storage
usage ratio_ is simply the drive space used by the file after erasure-encoding, divided by actual file size.

| Total Drives (N) | Data Drives (D) | Parity Drives (P) | Storage Usage Ratio |

var errDriveIsRoot = StorageErr("drive is part of root drive, will not be used")

// errFaultyRemoteDisk - remote disk is faulty.
var errFaultyRemoteDisk = StorageErr("remote drive is faulty")

// errFaultyDisk - disk is faulty.
var errFaultyDisk = StorageErr("drive is faulty")

// errDiskAccessDenied - we don't have write permissions on disk.
var errDiskAccessDenied = StorageErr("drive access denied")

				if deploymentID != "" {
					newFormat.ID = deploymentID
				}
				drive := pool.Endpoints[i*setDriveCount+j]
				fmtBytes, err := json.Marshal(newFormat)
				if err != nil {
					//nolint:gocritic
					log.Fatalf("failed to marshal format.json for %s: %v", drive.String(), err)
				}
				fmtJSON := filepath.Join(drive.Host, drive.Path, minioMetaBucket, "format.json")
				embedFileInZip(fmtZipW, fmtJSON, fmtBytes, 0o600)

- **MinIO creates erasure-coding sets of _2_ to _16_ drives per set.  The number of drives you provide in total must be a multiple of one of those numbers.**
- **MinIO chooses the largest EC set size which divides into the total number of drives or total number of nodes given - making sure to keep the uniform distribution i.e each node participates equal number of drives per set**.