Note
- The scope of this parameter is adjusted to the tenant level starting from V4.1.0.
- This parameter is available starting with V2.2.50.
Description
log_restore_concurrency specifies the concurrency level for log restore.
Note
Restore worker threads are created only when a tenant or standby tenant is being restored.
Privilege requirements
Query the parameter
The
systenant and all user tenants can query the value of this parameter by executing theSHOW PARAMETERSstatement or querying theGV$OB_PARAMETERSview.Modify the parameter
The
systenant and user tenants can modify this parameter.
Attributes
| Attribute | Description |
|---|---|
| Parameter type | Int |
| Default value | 0, which indicates that the adaptive log restore concurrency level of OceanBase Database is used.
NoteStarting from V4.2.0, the default value is adjusted from 1 to 0. |
| Value range | [0, 100]
NoteStarting from V4.2.0, the value range is adjusted from [1, 100] to [0, 100]. |
| 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
When the adaptive log restore concurrency level of OceanBase Database is used, the number of restore worker threads is adaptive to the max_cpu value of the tenant.
Examples
Set the log restore concurrency level to 5.
obclient> ALTER SYSTEM SET log_restore_concurrency = 5;