Note
The scope of this parameter is adjusted to the tenant level starting from V4.1.0.
Description
log_archive_concurrency specifies the concurrency of log archiving.
Privilege requirements
Query the parameter
systenants and all user tenants can query this parameter by using theSHOW PARAMETERSstatement or theGV$OB_PARAMETERSview.Modify the parameter
systenants and user tenants can modify this parameter.
Attributes
Attribute |
Description |
|---|---|
| Type | Int |
| Default value | 0, which indicates that the adaptive log archiving concurrency of OceanBase Database is used.
NoteStarting from V4.2.0, the default value of this parameter is adjusted from 1 to 0. |
| Value range | [0, 100]
NoteStarting from V4.2.0, the value range of this parameter 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
The number of archiving threads is calculated based on the adaptive value of max_cpu for the tenant:
- When
max_cpuis less than or equal to 8, the number of archiving threads ismax_cpu. - When
8 < max_cpu < 32, the number of archiving threads ismax(8, max_cpu/2). That is, ifmax_cpu/2is less than 8, the result is set to 8. - When
max_cpuis greater than or equal to 32, the number of archiving threads ismax(16, max_cpu/4). That is, ifmax_cpu/4is less than 16, the result is set to 16.
Examples
Change the log archiving concurrency of a MySQL-compatible tenant in the
systenant.obclient> ALTER SYSTEM SET log_archive_concurrency = 5 tenant = 'mysql';Change the log archiving concurrency of the current MySQL-compatible tenant.
obclient> ALTER SYSTEM SET log_archive_concurrency = 5;