Note
In OceanBase Database V4.x, the corresponding feature in MemStore memory management is no longer available. This parameter has been deprecated since OceanBase Database V4.2.0.
Description
global_write_halt_residual_memory specifies the threshold in percentage of global available memory. When the global available memory is smaller than the specified percentage, data writes to user tenants are suspended.
Note
The sys tenant is not affected.
Attributes
| Attribute | Description |
|---|---|
| Type | Integer |
| Default value | 30 |
| 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
The value of global_write_halt_residual_memory is in percentage with memory_limit - system_memory as the base. To be specific, the base is the total memory minus the memory reserved for the sys500 tenant. During the calculation of the available memory, the memory that the block cache can occupy is considered as the memory available to the MemStore.
Examples
Set the threshold of global available memory to 30%.
obclient> ALTER SYSTEM SET global_write_halt_residual_memory=30;