Read Replicas issues on Adobe Commerce Cloud 2.4.6 with MariaDB 10.6

This article provides solutions for unexpected behavior when using Read Replicas on Adobe Commerce Cloud 2.4.6 with MariaDB 10.6+.

Affected products and versions

• MariaDB 10.6+
• Adobe Commerce on cloud infrastructure 2.4.6

Issue

Non-critical reads are showing incorrect information.

Cause

The slave_parallel_mode config on the database was changed by default to optimistics when the value should be conservative, and the synchronous_replication value in Ece-Tools is defaulting to true when the value should be false.

Solution

1. Check that the slave_parallel_mode parameter is set to conservative (you will need to raise a support ticket if the value is not showing as conservative). To check, run the following command:

    MariaDB [main]> show variables like 'slave_parallel_mode';
    +---------------------+--------------+
    | Variable_name       | Value        |
    +---------------------+--------------+
    | slave_parallel_mode | conservative |
    +---------------------+--------------+
    1 row in set (0.001 sec)
   

2. Update .magento.env.yaml database configurations to:

       DATABASE_CONFIGURATION:
        _merge: true
           slave_connection:
               default:
                   synchronous_replication: false
   

For steps on updating the database configuration, refer to DATABASE_CONFIGURATION in the Deploy variables topic in the Commerce on Cloud Infrastructure Guide.

Related reading

• Configure environment variables for deployment in the Commerce on Cloud Infrastructure Guide.
• Best practices for database configuration in the Implementation Playbook.