Note
This parameter is available starting with V4.3.5 BP2.
Overview
io_scheduler_thread_count specifies the number of threads for the I/O isolation scheduling logic.
Privilege requirements
Query parameters
Both the
systenant and all user tenants can query this parameter using theSHOW PARAMETERSstatement or theGV$OB_PARAMETERSview.Modify parameters
Only the
systenant can modify this parameter. User tenants cannot modify it.
Attributes
Attribute |
Description |
|---|---|
| Parameter type | Int |
| Default Value | 4 |
| Value range | [1,16] |
| Modifiable | Yes, you can use the following methods:ALTER SYSTEM SETStatement modification. |
| Whether to restart the OBServer node for the change to take effect | Yes, you need to restart the OBServer node for the changes to take effect. |
Usage instructions
This parameter is used to dynamically adjust the number of threads for the I/O isolation scheduling logic. With this configuration, the system can flexibly adjust resource allocation based on specific business requirements, thereby optimizing performance.
Under normal circumstances, a thread can support approximately 100,000 IOPS. If the disk performance is good and can reach 400,000 IOPS, it is recommended to adjust the number of threads to 4. In a real production environment, it is recommended to determine the optimal number of threads through performance testing.
Configuration example
Set the number of threads for the I/O isolation scheduling logic to 8.
obclient> ALTER SYSTEM SET io_scheduler_thread_count = 8;