The OceanBase Database kernel supports more than ten types of resource requests, including both foreground and background tasks. Most background tasks have low priority, so their resource usage needs to be isolated. Resource isolation is enabled by default.
Because the built-in approach for freely configuring resource isolation for background tasks in Configure resource isolation within a tenant is complex, this section provides a recommended method. It simplifies configuration for background tasks by grouping resource request types.
Grouping resource request types
The current configuration of resource isolation is complex. To simplify it, you can group the resource request types. The following resource groups are used:
- CLOG log commit resource group: CLOG_HIGH_GROUP
- Compaction resource group: COMPACTION_HIGH_GROUP
- Background task resource group: BACKGROUND_GROUP
The following table shows the resource request types included in each resource group. For more details about the resource request types (background tasks), see Resource isolation overview.
Resource group |
Resource request types |
|---|---|
| CLOG_HIGH_GROUP | CLOG_HIGH |
| COMPACTION_HIGH_GROUP | COMPACTION_HIGH |
| BACKGROUND_GROUP |
|
Resource isolation strategy
Based on these groupings, you can define resource isolation policies for the resource groups. The recommended policies are shown in the following table.
Resource group |
MIN_IOPS |
MAX_IOPS |
IOPS_WEIGHT |
MAX_CPU |
CPU_WEIGHT |
|---|---|---|---|---|---|
| CLOG_HIGH_GROUP | 40 | 100 | 100 | 100 | 30 |
| COMPACTION_HIGH_GROUP | 30 | 100 | 50 | 100 | 70 |
| BACKGROUND_GROUP | 10 | 100 | 30 | 100 | 70 |
Note
Because the CLOG_HIGH background task directly affects business request latency, its I/O requirements are satisfied as much as possible. Therefore, set MIN_IOPS in CLOG_HIGH_GROUP to 40. This task does not require high CPU usage, so set CPU_WEIGHT to 30.
Configure resource isolation for background tasks
Prerequisites
CPU resource isolation depends on cgroups. If you need to control CPU resource isolation, configure the cgroup directory and enable the cgroup feature before you configure resource isolation for background tasks.
For details, see Configure cgroups.
Before configuring resource isolation for background tasks, calibrate disk performance and set IOPS for the tenant Unit.
Note
For V4.3.5, starting from V4.3.5 BP2, CPU and IOPS resource isolation no longer have a strict dependency on disk performance calibration.
Log in to the cluster as the
rootuser and switch to thesystenant.Calibrate disk performance.
Run the following command to trigger the disk calibration job:
obclient> ALTER SYSTEM RUN JOB "io_calibration";After the statement succeeds, run the following command to check the calibration progress:
obclient> SELECT * FROM oceanbase.GV$OB_IO_CALIBRATION_STATUS;Calibration may take 1–2 minutes to take effect after it completes. Then run the following command to view the calibration values:
obclient> SELECT * FROM oceanbase.GV$OB_IO_BENCHMARK;
Configure IOPS for the tenant Unit. Based on the disk calibration values on the OBServer nodes obtained in the previous step, use the 16 KB read calibration value as the upper limit for each node’s IOPS setting.
For more details, see Specify valid values for the MAX_IOPS and MIN_IOPS parameters of the tenant in Configure resource isolation within a tenant.
Procedure
Log in to the MySQL or Oracle tenant of the cluster as the tenant administrator of the user tenant.
Execute the following SQL statements to configure resource isolation for background tasks.
V4.3.5/V4.3.5 BP1V4.3.5 BP2 and later/*Create a plan*/ CALL DBMS_RESOURCE_MANAGER.CREATE_PLAN('GLOBAL_PLAN','plan for global'); /*Create the COMPACTION_HIGH_GROUP resource group*/ CALL DBMS_RESOURCE_MANAGER.CREATE_CONSUMER_GROUP( CONSUMER_GROUP => 'COMPACTION_HIGH_GROUP', COMMENT => 'COMPACTION_HIGH_GROUP'); CALL DBMS_RESOURCE_MANAGER.CREATE_PLAN_DIRECTIVE( PLAN => 'GLOBAL_PLAN', GROUP_OR_SUBPLAN => 'COMPACTION_HIGH_GROUP' , COMMENT => 'COMPACTION_HIGH_GROUP', MAX_IOPS => 100, MIN_IOPS => 30, WEIGHT_IOPS => 50,UTILIZATION_LIMIT => 100, MGMT_P1 => 70); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'COMPACTION_HIGH', 'COMPACTION_HIGH_GROUP'); /*Create the CLOG_HIGH_GROUP resource group*/ CALL DBMS_RESOURCE_MANAGER.CREATE_CONSUMER_GROUP( CONSUMER_GROUP => 'CLOG_HIGH_GROUP', COMMENT => 'CLOG_HIGH_GROUP'); CALL DBMS_RESOURCE_MANAGER.CREATE_PLAN_DIRECTIVE( PLAN => 'GLOBAL_PLAN', GROUP_OR_SUBPLAN => 'CLOG_HIGH_GROUP' , COMMENT => 'CLOG_HIGH_GROUP', MAX_IOPS => 100, MIN_IOPS => 40, WEIGHT_IOPS => 100, UTILIZATION_LIMIT => 100, MGMT_P1 => 30); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'CLOG_HIGH', 'CLOG_HIGH_GROUP'); /*Create the BACKGROUND_GROUP resource group*/ CALL DBMS_RESOURCE_MANAGER.CREATE_CONSUMER_GROUP( CONSUMER_GROUP => 'BACKGROUND_GROUP', COMMENT => 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.CREATE_PLAN_DIRECTIVE( PLAN => 'GLOBAL_PLAN', GROUP_OR_SUBPLAN => 'BACKGROUND_GROUP' , COMMENT => 'BACKGROUND_GROUP', MAX_IOPS => 100, MIN_IOPS => 10, WEIGHT_IOPS => 30, UTILIZATION_LIMIT => 100, MGMT_P1 => 70); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'COMPACTION_LOW', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'COMPACTION_MID', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'HA_LOW', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'HA_MID', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'HA_HIGH', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'DDL', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'DDL_HIGH', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'CLOG_LOW', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'CLOG_MID', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'OPT_STATS', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'GC_MACRO_BLOCK', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'IMPORT', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'SQL_AUDIT', 'BACKGROUND_GROUP'); /*Activate the plan*/ SET GLOBAL resource_manager_plan = 'GLOBAL_PLAN';/*Create a plan*/ CALL DBMS_RESOURCE_MANAGER.CREATE_PLAN('GLOBAL_PLAN','plan for global'); /*Create the COMPACTION_HIGH_GROUP resource group*/ CALL DBMS_RESOURCE_MANAGER.CREATE_CONSUMER_GROUP( CONSUMER_GROUP => 'COMPACTION_HIGH_GROUP', COMMENT => 'COMPACTION_HIGH_GROUP'); CALL DBMS_RESOURCE_MANAGER.CREATE_PLAN_DIRECTIVE( PLAN => 'GLOBAL_PLAN', GROUP_OR_SUBPLAN => 'COMPACTION_HIGH_GROUP' , COMMENT => 'COMPACTION_HIGH_GROUP', MAX_IOPS => 100, MIN_IOPS => 30, WEIGHT_IOPS => 50,UTILIZATION_LIMIT => 100, MGMT_P1 => 70); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'COMPACTION_HIGH', 'COMPACTION_HIGH_GROUP'); /*Create the CLOG_HIGH_GROUP resource group*/ CALL DBMS_RESOURCE_MANAGER.CREATE_CONSUMER_GROUP( CONSUMER_GROUP => 'CLOG_HIGH_GROUP', COMMENT => 'CLOG_HIGH_GROUP'); CALL DBMS_RESOURCE_MANAGER.CREATE_PLAN_DIRECTIVE( PLAN => 'GLOBAL_PLAN', GROUP_OR_SUBPLAN => 'CLOG_HIGH_GROUP' , COMMENT => 'CLOG_HIGH_GROUP', MAX_IOPS => 100, MIN_IOPS => 40, WEIGHT_IOPS => 100, UTILIZATION_LIMIT => 100, MGMT_P1 => 30); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'CLOG_HIGH', 'CLOG_HIGH_GROUP'); /*Create the BACKGROUND_GROUP resource group*/ CALL DBMS_RESOURCE_MANAGER.CREATE_CONSUMER_GROUP( CONSUMER_GROUP => 'BACKGROUND_GROUP', COMMENT => 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.CREATE_PLAN_DIRECTIVE( PLAN => 'GLOBAL_PLAN', GROUP_OR_SUBPLAN => 'BACKGROUND_GROUP' , COMMENT => 'BACKGROUND_GROUP', MAX_IOPS => 100, MIN_IOPS => 10, WEIGHT_IOPS => 30, UTILIZATION_LIMIT => 100, MGMT_P1 => 70); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'COMPACTION_LOW', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'COMPACTION_MID', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'HA_LOW', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'HA_MID', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'HA_HIGH', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'DDL', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'DDL_HIGH', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'CLOG_LOW', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'CLOG_MID', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'OPT_STATS', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'GC_MACRO_BLOCK', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'IMPORT', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'SQL_AUDIT', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'MVIEW', 'BACKGROUND_GROUP'); CALL DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING('FUNCTION', 'REPLAY_HIGH', 'BACKGROUND_GROUP'); /*Activate the plan*/ SET GLOBAL resource_manager_plan = 'GLOBAL_PLAN';
References
This topic provides only the recommended configuration method for resource isolation of background tasks. For information about how to configure resource isolation for other types within the tenant, see the following topics: