Note
The parameter name has been changed from merge_thread_count to compaction_low_thread_score since OceanBase Database V4.0.0.
Description
merge_thread_count specifies the number of worker threads for a daily compaction.
Limitations
Query the parameter
In the
systenant or a user tenant, you can execute theSHOW PARAMETERSstatement to query the parameter or query theGV$OB_PARAMETERSview for the parameter. In thesystenant, you can also query theinformation_schema.PARAMETERSview for the parameter.Modify the parameter
You can modify the parameter only in the
systenant.
Attributes
| Attribute | Description |
|---|---|
| Type | Integer |
| Default value | 0 |
| Value range | [0, 256] |
| Modifiable | Yes. You can use the ALTER SYSTEM SET statement to modify the parameter. |
| Effective upon OBServer node restart | No. The setting takes effect immediately. |
Considerations
If the value of this parameter is 0, the formula for calculating the number of worker threads for a compaction is min{10,cpu_cnt}, where cpu_cnt indicates the number of CPU cores in the system.
Example
obclient> ALTER SYSTEM SET merge_thread_count=100;