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DOCAPI-5203: Fix in terms of direct I/O.

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BayoNet 2019-03-05 13:16:45 +03:00
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2 changed files with 2 additions and 2 deletions
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docs/en/operations/settings/settings.md
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@ -177,7 +177,7 @@ Any positive integer.
## min_bytes_to_use_direct_io {#settings-min_bytes_to_use_direct_io} ## min_bytes_to_use_direct_io {#settings-min_bytes_to_use_direct_io}
The minimum data volume to be read from storage required for using of the direct I/O interface of the storage disk. The minimum data volume to be read from storage required for using of the direct I/O access to the storage disk.
ClickHouse uses this setting when selecting the data from tables. If summary storage volume of all the data to be read exceeds `min_bytes_to_use_direct_io` bytes, then ClickHouse reads the data from the storage disk with `O_DIRECT` option. ClickHouse uses this setting when selecting the data from tables. If summary storage volume of all the data to be read exceeds `min_bytes_to_use_direct_io` bytes, then ClickHouse reads the data from the storage disk with `O_DIRECT` option.

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docs/en/operations/table_engines/mergetree.md
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@ -70,7 +70,7 @@ For a description of request parameters, see [request description](../../query_l
- `SETTINGS` — Additional parameters that control the behavior of the `MergeTree`: - `SETTINGS` — Additional parameters that control the behavior of the `MergeTree`:
- `index_granularity` — The granularity of an index. The number of data rows between the "marks" of an index. By default, 8192. The list of all available parameters you can see in [MergeTreeSettings.h](https://github.com/yandex/ClickHouse/blob/master/dbms/src/Storages/MergeTree/MergeTreeSettings.h). - `index_granularity` — The granularity of an index. The number of data rows between the "marks" of an index. By default, 8192. The list of all available parameters you can see in [MergeTreeSettings.h](https://github.com/yandex/ClickHouse/blob/master/dbms/src/Storages/MergeTree/MergeTreeSettings.h).
- `min_merge_bytes_to_use_direct_io` — The minimum data volume for merge operation required for using of the direct I/O interface of the storage disk. During the merging of the data parts, ClickHouse calculates summary storage volume of all the data to be merged. If the volume exceeds `min_merge_bytes_to_use_direct_io` bytes, thеn ClickHouse reads and writes the data using direct I/O interface (`O_DIRECT` option) to the storage disk. If `min_merge_bytes_to_use_direct_io = 0`, then the direct I/O is disabled. Default value: `10 * 1024 * 1024 * 1024` bytes. - `min_merge_bytes_to_use_direct_io` — The minimum data volume for merge operation required for using of the direct I/O access to the storage disk. During the merging of the data parts, ClickHouse calculates summary storage volume of all the data to be merged. If the volume exceeds `min_merge_bytes_to_use_direct_io` bytes, thеn ClickHouse reads and writes the data using direct I/O interface (`O_DIRECT` option) to the storage disk. If `min_merge_bytes_to_use_direct_io = 0`, then the direct I/O is disabled. Default value: `10 * 1024 * 1024 * 1024` bytes.
**Example of sections setting** **Example of sections setting**