ALTER RESOURCE UNIT

Purpose

The ALTER RESOURCE UNIT statement is used to modify the resource specifications of a resource unit. Modifying resource specifications mainly involves increasing or decreasing CPU, memory, and log disk capacity.

Limitations and considerations

Before modifying the resource specifications, if the resource unit is being used by a tenant, the following considerations apply:

• If you want to increase the resource specifications, ensure that each node where the resource unit resides has sufficient remaining resources available for allocation.

  You can query the GV$OB_SERVERS view to check the total and allocated resources on each node. For more information, see View tenant and resource information.

• If you want to decrease the resource specifications, ensure that the total resources after modification (CPU, memory, and log disk capacity) are greater than or equal to the current resources used by the tenant.

Privilege requirements

Only the root user of the sys tenant (root@sys) can modify the resource specifications of a resource unit. Other tenants do not support modifying resource specifications.

Statement

ALTER RESOURCE UNIT unit_name
MEMORY_SIZE [=] 'size_value',
MAX_CPU [=] cpu_num,
[MIN_CPU [=] cpu_num,]
[MAX_IOPS [=] iops_num,]
[MIN_IOPS [=] iops_num,]
[IOPS_WEIGHT [=]iopsweight,]
[MAX_NET_BANDWIDTH [=] bandwidth_num,]
[NET_BANDWIDTH_WEIGHT [=] bandwidth_weight_num,]
[DATA_DISK_SIZE [=] 'size_value',]
[LOG_DISK_SIZE [=] 'size_value'];

Parameters

Examples

1. View the resource specifications of the resource unit unit1.

   obclient(root@sys)[oceanbase]> SELECT * FROM oceanbase.DBA_OB_UNIT_CONFIGS WHERE NAME='unit1';
   

   The query result is as follows:

   +----------------+-------+----------------------------+----------------------------+---------+---------+-------------+---------------+----------------+----------+----------+-------------+-------------------+----------------------+
   | UNIT_CONFIG_ID | NAME  | CREATE_TIME                | MODIFY_TIME                | MAX_CPU | MIN_CPU | MEMORY_SIZE | LOG_DISK_SIZE | DATA_DISK_SIZE | MAX_IOPS | MIN_IOPS | IOPS_WEIGHT | MAX_NET_BANDWIDTH | NET_BANDWIDTH_WEIGHT |
   +----------------+-------+----------------------------+----------------------------+---------+---------+-------------+---------------+----------------+----------+----------+-------------+-------------------+----------------------+
   |           1001 | unit1 | 2025-05-28 11:19:39.116490 | 2025-05-28 11:19:39.116490 |       4 |       4 |  5368709120 |   10737418240 |           NULL |     1280 |     1024 |           1 |           5242880 |                   10 |
   +----------------+-------+----------------------------+----------------------------+---------+---------+-------------+---------------+----------------+----------+----------+-------------+-------------------+----------------------+
   1 row in set
   

2. Modify the resource specifications of the resource unit unit1 to 2 CPU cores, 5 GB of memory, a maximum network bandwidth of 4 M per resource unit, and a network bandwidth weight of 8.

   obclient(root@sys)[oceanbase]> ALTER RESOURCE UNIT unit1 MAX_CPU 2, MIN_CPU 2, MEMORY_SIZE '5G', MAX_NET_BANDWIDTH '4M', NET_BANDWIDTH_WEIGHT 8;
   

3. After the modification is successful, view the resource specifications of the resource unit unit1 again.

   obclient(root@sys)[oceanbase]> SELECT * FROM oceanbase.DBA_OB_UNIT_CONFIGS WHERE NAME='unit1';
   

   The query result is as follows:

   +----------------+-------+----------------------------+----------------------------+---------+---------+-------------+---------------+----------------+----------+----------+-------------+-------------------+----------------------+
   | UNIT_CONFIG_ID | NAME  | CREATE_TIME                | MODIFY_TIME                | MAX_CPU | MIN_CPU | MEMORY_SIZE | LOG_DISK_SIZE | DATA_DISK_SIZE | MAX_IOPS | MIN_IOPS | IOPS_WEIGHT | MAX_NET_BANDWIDTH | NET_BANDWIDTH_WEIGHT |
   +----------------+-------+----------------------------+----------------------------+---------+---------+-------------+---------------+----------------+----------+----------+-------------+-------------------+----------------------+
   |           1001 | unit1 | 2025-05-28 11:19:39.116490 | 2025-05-28 11:31:15.005869 |       2 |       2 |  5368709120 |   10737418240 |           NULL |     1280 |     1024 |           1 |           4194304 |                    8 |
   +----------------+-------+----------------------------+----------------------------+---------+---------+-------------+---------------+----------------+----------+----------+-------------+-------------------+----------------------+
   1 row in set
   

References

View tenant and resource information