# `NodesIoStatDevice` [interface-NodesIoStatDevice]

| Name | Type | Description |
| - | - | - |
| `device_name` | string | The Linux device name. |
| `operations` | [long](./long.md) | The total number of read and write operations for the device completed since starting Elasticsearch. |
| `read_kilobytes` | [long](./long.md) | The total number of kilobytes read for the device since starting Elasticsearch. |
| `read_operations` | [long](./long.md) | The total number of read operations for the device completed since starting Elasticsearch. |
| `write_kilobytes` | [long](./long.md) | The total number of kilobytes written for the device since starting Elasticsearch. |
| `write_operations` | [long](./long.md) | The total number of write operations for the device completed since starting Elasticsearch. |