Alibaba Cloud provides enhanced SSDs (ESSDs), which come in different performance levels (PLs). ESSDs of PL1 are designed based on the new-generation distributed block storage architecture. An ESSD of PL1 delivers higher IOPS, higher throughput, and more stable I/O performance than a standard SSD. However, the fee for an ESSD of PL1 is the same as the fee for a standard SSD in most Alibaba Cloud regions. You can upgrade the storage type of an ApsaraDB RDS for MySQL instance from standard SSDs to ESSDs of PL1 to increase cost-effectiveness.

Prerequisites

  • The RDS instance is in the Running state.
  • The RDS instance runs one of the following MySQL versions and RDS editions:
    • MySQL 8.0 on RDS High-availability Edition or RDS Basic Edition with standard SSDs
    • MySQL 5.7 on RDS High-availability Edition or RDS Basic Edition with standard SSDs
  • The minor engine version of the RDS instance is 20201031 or later. This requirement must be met if the RDS instance runs RDS Basic Edition. For more information about how to upgrade the minor engine version of an RDS instance, see Update the minor engine version of an ApsaraDB RDS for MySQL instance.

Performance comparison between ESSDs of PL1 and standard SSDs

The fee for an ESSD of PL1 is the same as the fee for a standard SSD. However, the ESSD of PL1 delivers significantly higher performance than the standard SSD. The following table describes the differences between ESSDs of PL1 and standard SSDs.

Comparison item ESSD of PL1 Standard SSD
Maximum capacity per 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

Billing rules

When you upgrade the storage type of an RDS instance, the upgrade fee covers the following items:
  • Backup: To ensure data security, ApsaraDB RDS performs a temporary full backup on the data of the RDS instance and retains the backup file for seven days. You may be charged for the backup fee. For more information, see Backup storage pricing of an ApsaraDB RDS for MySQL instance.
  • ESSDs: You may be charged for the ESSD fee, which varies based on the region of the RDS instance. You can view the fee when you perform the upgrade.

Impacts

  • When you upgrade the storage type, a transient connection that lasts approximately 30 seconds occurs. We recommend that you perform the upgrade during off-peak hours and make sure that your application is configured to automatically reconnect to the RDS instance.
  • When the storage type is being upgraded, you cannot perform operations on the RDS instance. For example, you cannot upgrade or downgrade the RDS instance, upgrade the database engine version of the RDS instance, or migrate the RDS instance across zones.

Procedure

  1. Access RDS Instances, select a region at the top, and then click the ID of the target RDS instance.
  2. In the Basic Information section of the page that appears, click the button for upgrading the storage type next to Storage Type.
    Note If the button cannot be found, you must check whether the RDS instance meets all requirements that are specified in the "Prerequisites" section of this topic.
  3. On the tab that appears, read and select the terms of service, click Pay Now, and then complete the payment.
    The status of the RDS instance changes to Upgrading/Downgrading. When the status of the RDS instance changes back to Running, the upgrade is complete.

FAQ

  • Why am I unable to select the ESSD storage type for my RDS instance?

    If the zones in which your RDS instance resides cannot provide sufficient resources or do not support ESSDs, you cannot select the ESSD storage type for your RDS instance. In this case, you must update the minor engine version of your RDS instance and migrate your RDS instance to zones in which ESSDs are supported before you upgrade the storage type. 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.

  • When I upgrade the storage type of my RDS instance, does ApsaraDB RDS automatically upgrade the storage types of the read-only RDS instances that are attached to my RDS instance?

    No, ApsaraDB RDS does not automatically upgrade the storage types of the read-only RDS instances. You must repeat the procedure in this topic to manually upgrade the storage type of each read-only RDS instance.

  • When I change the specifications of my RDS instance, are my online workloads interrupted?

    For more information, see the "Impacts" section of this topic.

  • Do the endpoints and IP addresses of my RDS instance change after I change the storage type?

    The endpoints of your RDS instance remain unchanged after you change the storage type. An example endpoint is rm-bpxxxxx.mysql.rds.aliyuncs.com. However, the IP addresses that are associated with the endpoints may change. We recommend that you add the endpoints rather than the IP addresses to your application.

  • Which factors affect the amount of time that is required to change the storage type of my RDS instance?

    For more information, see Which factors affect the time that is required to change the specifications of my ApsaraDB RDS for MySQL instance?

Related operations

Operation Description
ModifyDBInstanceSpec Changes the specifications of an ApsaraDB RDS instance.