Note
For V4.1.0, this parameter is available starting with V4.1.0.
Description
cpu_quota_concurrency specifies the maximum number of active threads allowed per CPU quota for a tenant.
Privilege requirements
Query the parameter
The
systenant and all user tenants can use theSHOW PARAMETERSstatement or theGV$OB_PARAMETERSview to query this parameter.Modify the parameter
The
systenant and user tenants can modify this parameter.
Attributes
| Attribute | Description |
|---|---|
| Type | DOUBLE |
| Default value | 4 |
| Value range | [1, 20]
NoteFor V4.2.0, the value range of this parameter is adjusted from [1, 10] to [1, 20]. |
| Modifiable | Yes. You can use the ALTER SYSTEM SET statement to modify the parameter.
NoticeIt is recommended to avoid modifying this parameter because reducing its value may affect performance and even cause stability risks, while increasing it may increase memory usage and lead to high CPU load, which carries certain risks. |
| Effective upon OBServer node restart | No. The setting takes effect immediately. |
Considerations
The number of threads that can be handled by a tenant is controlled by the cpu_quota_concurrency and workers_per_cpu_quota parameters. When setting these parameters, ensure that workers_per_cpu_quota > cpu_quota_concurrency. Here's an explanation of the parameters:
workers_per_cpu_quotaspecifies the maximum number of worker threads that can be allocated per CPU for a tenant. For more information aboutworkers_per_cpu_quota, see workers_per_cpu_quota.cpu_quota_concurrencyspecifies the maximum number of active threads allowed per CPU quota for a tenant, which is the concurrency level.
Examples
Set the maximum number of active threads allowed per CPU quota for a tenant to 4.
obclient> ALTER SYSTEM SET cpu_quota_concurrency=4;