Alibaba Cloud provides enhanced SSDs (ESSDs) at different performance levels (PLs). The ESSDs of PL1 are designed based on a new generation of distributed block storage architecture. ESSDs require the same price as standard SSDs in most regions, but deliver higher IOPS, higher throughput, and more stable I/O performance than standard SSDs. From July 01, 2022, Alibaba Cloud gradually phases out the standard SSD storage type for specific database engines in ApsaraDB RDS. This makes it easier to select the storage type for an ApsaraDB RDS instance.
Specific database engines and end-of-sale dates
Database engine | End-of-sale date |
---|---|
MySQL | July 01, 2022 |
MariaDB TX | July 01, 2022 |
PostgreSQL | July 06, 2022 |
SQL Server | July 08, 2022 |
Impacts and suggestions
- When you purchase an ApsaraDB RDS instance that runs one of the following database
engines, you cannot select the standard SSD storage type:
- MySQL
- PostgreSQL
- MariaDB TX
- SQL Server
Note The standard SSD storage type is gradually phased out. You may still be able to select the standard SSD storage type after July 01, 2022. However, we recommend that you select ESSDs. - If your existing RDS instance uses the standard SSD storage type, you can continue
to use the configured standard SSDs. However, we recommend that you upgrade the storage
type of your RDS instance to ESSDs of PL1 to experience better read and write performance:
Note When you upgrade the storage type, you are charged a specific fee. The fee varies based on the region in which your RDS instance resides. You can view the fee when you perform the upgrade.
Database engine Upgrade operation MySQL and MariaDB TX - When you change the specifications of your RDS instance, select ESSD of PL1 for the storage type. For more information, see Change the specifications of an ApsaraDB RDS for MySQL instance.
- When you perform the following operations, ApsaraDB RDS automatically upgrades the storage type of your RDS instance to ESSDs of PL1.
- If the zone in which your RDS instance resides cannot provide sufficient resources or does not support ESSDs, you cannot change the specification of your RDS instance. If your RDS instance resides in a zone in which ESSDs are not supported, you must update the minor engine version of your RDS instance and migrate your RDS instance to a zone in which ESSDs are supported. Then, you can change the specification of your RDS instance. For more information, see Update the minor engine version of an ApsaraDB RDS for MySQL instance and Migrate an ApsaraDB RDS for MySQL instance across zones in the same region.
PostgreSQL - When you change the specifications of your RDS instance, select ESSD of PL1 for the storage type. For more information, see Change the specifications of an ApsaraDB RDS for MySQL instance.
- When you upgrade the major engine version of your RDS instance, ApsaraDB RDS automatically upgrades the storage type of your instance to ESSDs of PL1. For more information, see Upgrade the major engine version of an ApsaraDB RDS for PostgreSQL instance.
- If the zone in which your RDS instance resides cannot provide sufficient resources or does not support ESSDs, you cannot change the specification of your RDS instance. If your RDS instance resides in a zone in which ESSDs are not supported, you must update the minor engine version of your RDS instance and migrate your RDS instance to a zone in which ESSDs are supported. Then, you can change the specification of your RDS instance. For more information, see Migrate an ApsaraDB RDS for PostgreSQL instance across zones in the same region.
SQL Server - When you change the specifications of your RDS instance, select ESSD of PL1 for the storage type. For more information, see Change the specifications of an ApsaraDB RDS for SQL Server instance.
- When you upgrade the major engine version of your RDS instance or when you upgrade your RDS instance that runs RDS Basic Edition to RDS High-availability Edition, ApsaraDB RDS automatically upgrades the storage type of your instance to ESSDs of PL1. For more information, see Upgrade an instance from SQL Server 2012 to SQL Server 2016 and Upgrade an ApsaraDB RDS for SQL Server instance from Basic Edition to High-availability Edition.
- If the zone in which your RDS instance resides cannot provide sufficient resources or does not support ESSDs, you cannot change the specification of your RDS instance. If your RDS instance resides in a zone in which ESSDs are not supported, you must update the minor engine version of your RDS instance and migrate your RDS instance to a zone in which ESSDs are supported. Then, you can change the specification of your RDS instance. For more information, see Migrate an ApsaraDB RDS for PostgreSQL instance across zones in the same region.
Performance comparison between ESSDs of PL1 and standard SSDs
ESSDs of PL1 require the same price as standard SSDs in most regions but deliver higher performance. The following table describes the specific performance differences.
Item | ESSD of PL1 | Standard SSD |
---|---|---|
Maximum capacity of a single SSD (GiB) | 20 to 32,768 | 32,768 |
Maximum IOPS | 50,000 | 25,000 |
Maximum throughput (MB/s) | 350 | 300 |
IOPS per SSD | min{1,800 + 50 × Capacity, 50,000} | min{1,800 + 30 × Capacity, 25,000} |
Throughput per SSD (MB/s) | min{120 + 0.5 × Capacity, 350} | min{120 + 0.5 × Capacity, 300} |
Average random write latency per connection (ms) | 0.2 | 0.5 to 2 |