Note
This parameter is available starting with V1.4.
Description
freeze_trigger_percentage specifies the threshold percentage of the tenant's memory usage for triggering a freeze.
Privilege requirements
Query the parameter
The
systenant and all user tenants can query this parameter by using theSHOW PARAMETERSstatement or theGV$OB_PARAMETERSview.Modify the parameter
The
systenant and user tenants can modify this parameter.
Attributes
| Attribute | Description |
|---|---|
| Type | Int |
| Default value | 20
NoteStarting from V4.0.0, the default value is adjusted from 70 to 20. |
| Value range | (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
You can adjust the proportion of MemStore memory in the tenant's memory by using the following parameter:
When the active MemStore memory usage of a tenant reaches
freeze_trigger_percentage * memstore_limit(wherememstore_limit = tenant memory * memstore_limit_percentage), the system automatically triggers a freeze (as a prerequisite for a dump) and then schedules a dump. After the dump, the system releases the occupied MemStore memory.When memory is insufficient, you can increase the value of
memstore_limit_percentageand decrease the value offreeze_trigger_percentageto temporarily expand the memory and expedite the dump process. Thememstore_limit_percentageparameter specifies the proportion of the tenant's memory that can be used for MemStore writes. The default value is 0, indicating that the system automatically adjusts the proportion of memory available for MemStore writes.
Examples
Set the threshold percentage of the tenant's memory usage for triggering a freeze to 20.
obclient> ALTER SYSTEM SET freeze_trigger_percentage=20;