ApsaraDB for OceanBase supports multiple parameter types, including BOOL, CAPACITY, DOUBLE, INT, MOMENT, STRING, STRING_LIST, and TIME.
The following table describes the main parameter types and default units.
Parameter |
Description |
|---|---|
| BOOL | The Boolean type. Valid values: true and false. |
| CAPACITY | The capacity. The unit can be byte, kilobyte, megabyte, gigabyte, terabyte, or petabyte. The unit is not case-sensitive. By default, the unit is megabyte. |
| DOUBLE | The double-precision floating-point type. A 64-bit value of this type is accurate to 15 digits after the decimal point and has 16 significant digits at most. |
| INT | The 64-bit integer type. The value can be a positive integer, negative integer, or zero. |
| MOMENT | The time point. The value is in the hh:mm format, for example, 02:00. You can also set this parameter to disable. This indicates that the time is not specified. MOMENT is used only in the major_freeze_duty_time parameter. |
| STRING | The string type. You can enter a string based on the parameter description of ApsaraDB for OceanBase. |
| STRING_LIST | A list of strings. Strings are separated with semicolons ;. |
| TIME | The time type. The unit can be microsecond, millisecond, second, minute, hour, or day. By default, the unit is second. The unit is not case-sensitive. |
Parameter semantics changes in shared storage mode
When the cluster is an AI cluster (in shared storage mode, ob_startup_mode=shared_storage), the semantics of some cluster parameters change. The details are as follows:
Parameter |
Description |
|---|---|
| datafile_size | In shared storage mode, this parameter indicates the cache space size, not the data file size. |
| datafile_disk_percentage | In shared storage mode, this parameter indicates the percentage of the cache space. |
| datafile_next | This parameter is not supported in shared storage mode. |
| datafile_maxsize | This parameter is not supported in shared storage mode. |
| _datafile_usage_upper_bound_percentage | This parameter is not supported in shared storage mode. |
| _datafile_usage_lower_bound_percentage | This parameter is not supported in shared storage mode. |
In addition, the following tenant-level parameters are introduced in shared storage mode:
Parameter |
Description |
|---|---|
| shared_log_retention | The retention period for shared logs. Default value: 1 day. Value range: [0d, 14d]. |
| read_cache_disk_percentage | The percentage of disk space used by the read cache. Default value: 40. Value range: [0, 90]. |
| cache_disk_memory_limit | The memory limit for the cache disk. Default value: 10. Value range: [5, 50]. |