Note
This variable is avaiable starting with V1.4.
Description
ob_plan_cache_evict_low_percentage specifies the percentage of the maximum memory size that is used to stop evicting plan cache.
Privilege requirements
Query variables
systenant and all user tenants can execute theSHOW VARIABLESstatement or query theSYS.TENANT_VIRTUAL_GLOBAL_VARIABLEview (Oracle mode) or theinformation_schema.GLOBAL_VARIABLESview (MySQL mode) to view the value of a global system variable.Modify variables
systenant can modify the value of a global system variable.MySQL user tenants must have the
SUPERorALTER SYSTEMprivilege to modify the value of a global system variable.Oracle user tenants must have the
ALTER SYSTEMprivilege to modify the value of a global system variable.
Attributes
| Attribute | Description |
|---|---|
| Type | Int |
| Default value | 50 |
| Value range | [0, 100] |
| Scope | Global |
| Modifiable | Yes. You can execute the SET statement to modify the value. |
Usage notes
The size of memory used to stop evicting plan cache (low watermark of plan evict) = absolute value of maximum memory size × ob_plan_cache_evict_low_percentage / 100. For more information about the absolute value of the maximum memory size, see ob_plan_cache_percentage.
Examples
Set the percentage of the maximum memory size that is used to stop evicting plan cache to 50.
obclient> SET GLOBAL ob_plan_cache_evict_low_percentage =50;