--- slug: /en/operations/system-tables/disks --- # disks Contains information about disks defined in the [server configuration](../../engines/table-engines/mergetree-family/mergetree.md#table_engine-mergetree-multiple-volumes_configure). Columns: - `name` ([String](../../sql-reference/data-types/string.md)) — Name of a disk in the server configuration. - `path` ([String](../../sql-reference/data-types/string.md)) — Path to the mount point in the file system. - `free_space` ([UInt64](../../sql-reference/data-types/int-uint.md)) — Free space on disk in bytes. - `total_space` ([UInt64](../../sql-reference/data-types/int-uint.md)) — Disk volume in bytes. - `unreserved_space` ([UInt64](../../sql-reference/data-types/int-uint.md)) — Free space which is not taken by reservations (`free_space` minus the size of reservations taken by merges, inserts, and other disk write operations currently running). - `keep_free_space` ([UInt64](../../sql-reference/data-types/int-uint.md)) — Amount of disk space that should stay free on disk in bytes. Defined in the `keep_free_space_bytes` parameter of disk configuration. **Example** ```sql SELECT * FROM system.disks; ``` ```response ┌─name────┬─path─────────────────┬───free_space─┬──total_space─┬─keep_free_space─┐ │ default │ /var/lib/clickhouse/ │ 276392587264 │ 490652508160 │ 0 │ └─────────┴──────────────────────┴──────────────┴──────────────┴─────────────────┘ 1 rows in set. Elapsed: 0.001 sec. ```