CREATE RESOURCE GROUP
You can use the CREATE RESOURCE GROUP
statement to create a resource group.
Synopsis
- CreateResourceGroupStmt
- IfNotExists
- ResourceGroupName
- ResourceGroupOptionList
- DirectResourceGroupOption
- ResourceGroupPriorityOption
CreateResourceGroupStmt ::=
"CREATE" "RESOURCE" "GROUP" IfNotExists ResourceGroupName ResourceGroupOptionList
IfNotExists ::=
('IF' 'NOT' 'EXISTS')?
ResourceGroupName ::=
Identifier
ResourceGroupOptionList ::=
DirectResourceGroupOption
| ResourceGroupOptionList DirectResourceGroupOption
| ResourceGroupOptionList ',' DirectResourceGroupOption
DirectResourceGroupOption ::=
"RU_PER_SEC" EqOpt stringLit
| "PRIORITY" EqOpt ResourceGroupPriorityOption
| "BURSTABLE"
ResourceGroupPriorityOption ::=
LOW
| MEDIUM
| HIGH
The resource group name parameter (ResourceGroupName
) must be globally unique.
TiDB supports the following DirectResourceGroupOption
, where Request Unit (RU) is a unified abstraction unit in TiDB for CPU, IO, and other system resources.
Option | Description | Example |
---|---|---|
RU_PER_SEC | Rate of RU backfilling per second | RU_PER_SEC = 500 indicates that this resource group is backfilled with 500 RUs per second |
PRIORITY | The absolute priority of tasks to be processed on TiKV | PRIORITY = HIGH indicates that the priority is high. If not specified, the default value is MEDIUM . |
BURSTABLE | If the BURSTABLE attribute is set, TiDB allows the corresponding resource group to use the available system resources when the quota is exceeded. |
Examples
Create two resource groups rg1
and rg2
.
DROP RESOURCE GROUP IF EXISTS rg1;
Query OK, 0 rows affected (0.22 sec)
CREATE RESOURCE GROUP IF NOT EXISTS rg1
RU_PER_SEC = 100
PRIORITY = HIGH
BURSTABLE;
Query OK, 0 rows affected (0.08 sec)
CREATE RESOURCE GROUP IF NOT EXISTS rg2
RU_PER_SEC = 200;
Query OK, 0 rows affected (0.08 sec)
SELECT * FROM information_schema.resource_groups WHERE NAME ='rg1' or NAME = 'rg2';
+------+------------+----------+-----------+
| NAME | RU_PER_SEC | PRIORITY | BURSTABLE |
+------+------------+----------+-----------+
| rg1 | 100 | HIGH | YES |
| rg2 | 200 | MEDIUM | NO |
+------+------------+----------+-----------+
2 rows in set (1.30 sec)
MySQL compatibility
MySQL also supports CREATE RESOURCE GROUP. However, the acceptable parameters are different from that of TiDB so that they are not compatible.