Starting June 20, 2024, ApsaraDB RDS for MySQL provides standard read-only RDS instances that run RDS Basic Edition. If your database system receives a small number of write requests but a large number of read requests, a single primary RDS instance may become overloaded by the read requests. This may interrupt your workloads. To offload read requests from the primary RDS instance, you can create one or more read-only RDS instances. Read-only RDS instances help increase the read capability of your database system and the throughput of your application.
Supported engine versions
Read-only RDS instances that run RDS Basic Edition can be created for a primary RDS instance that runs MySQL 5.7 or MySQL 8.0.
RDS Basic Edition: The database system consists only of a primary RDS instance. Computing is decoupled from storage.
Standard: Standard RDS instances use the x86 architecture and support larger capacity and more instance families.
Effective date
June 20, 2024
Billing rules
The subscription and pay-as-you-go billing methods are supported.
Scenarios
If a primary RDS instance is overloaded, you can create read-only RDS instances to offload read requests from the primary RDS instance.
If a primary RDS instance is temporarily unavailable due to backup or maintenance reasons, you can use read-only RDS instances to process read requests. This helps ensure business continuity.
In scenarios such as report analysis, you can use read-only RDS instances to query and analyze large amounts of data. This does not affect the primary RDS instance.
If you use the read/write splitting feature, you can use read-only RDS instances to prevent read/write lock contention and improve system performance and throughput.
If you use RDS Basic Edition, the database system consists only of one RDS instance. Computing is decoupled from storage to increase cost-effectiveness. No secondary RDS instance is provided as a hot standby for the RDS instance. If the RDS instance fails or you restart the RDS instance, change the instance specifications, or upgrade the database engine version, your database service may become unavailable for a long period of time. If you require high service availability, we recommend that you use RDS High-availability Edition. For more information, see RDS Basic Edition and RDS High-availability Edition.
Supported specifications
RDS edition | Instance family | Instance type | Number of CPU cores and memory capacity | Maximum number of connections | Storage | |
Maximum I/O bandwidth (Mbit/s) | Storage capacity | |||||
RDS Basic Edition | General-purpose | mysqlro.n2.small.c | 1 core, 2 GB | 2,000 | 1,024 |
|
mysqlro.n2.medium.c | 2 cores, 4 GB | 4,000 | 1,024 | |||
mysqlro.n4.medium.c | 2 cores, 8 GB | 6,000 | 1,024 | |||
mysqlro.n8.medium.c | 2 cores, 16 GB | 8,000 | 1,024 | |||
mysqlro.n2.large.c | 4 cores, 8 GB | 6,000 | 1,536 | |||
mysqlro.n4.large.c | 4 cores, 16 GB | 8,000 | 1,536 | |||
mysqlro.n8.large.c | 4 cores, 32 GB | 12,000 | 1,536 | |||
mysqlro.n2.xlarge.c | 8 cores, 16 GB | 8,000 | 2,048 | |||
mysqlro.n4.xlarge.c | 8 cores, 32 GB | 10,000 | 2,048 | |||
mysqlro.n8.xlarge.c | 8 cores, 64 GB | 16,000 | 2,048 | |||
Purchase a read-only RDS instance
Log on to the ApsaraDB RDS console. In the top navigation bar, select the region in which the required RDS instance resides. Then, find the RDS instance and click the instance ID.
In the Instance Distribution section of the Basic Information page, click Add to the right of the Read-only Instance parameter.
On the Read-only Instance buy page, set the Edition parameter to Basic Edition. For more information, see Create a read-only ApsaraDB RDS for MySQL instance.