Use the parameter diagnostics feature - ApsaraDB RDS - Alibaba Cloud Documentation Center

Database Autonomy Service (DAS) provides the parameter diagnostics feature for ApsaraDB RDS for MySQL. You can use this feature to diagnose the parameters of your ApsaraDB RDS for MySQL instance. You can view the static parameter diagnostic results and the parameter modification history within the last seven days.

Background information

Database performance optimization is one of the most important researches in industry and academia. In addition to optimization to business code and SQL statements, including index optimization, parameter tuning is an efficient manner to improve database performance.

Prerequisites

The RDS instance runs MySQL 5.6, MySQL 5.7, or MySQL 8.0.

Note

If your RDS instance runs RDS Basic Edition, you can perform parameter diagnostics in the DAS console. For more information, see Parameter diagnostics.

Limits

Only one parameter diagnostics task can be triggered within 3 minutes.
The parameter diagnostics feature only diagnoses the parameters that can be modified in the ApsaraDB RDS console and provides diagnostics results. The feature does not directly modify parameters.
If two consecutive parameter diagnostics tasks span a short period of time, the returned results may be the same.

Implementation

Obtain the instance topology and separately diagnose the parameters of the primary RDS instance and the read-only RDS instances (if any).
Diagnose instance parameters based on the instance status, parameter template, reference concepts of additional parameters, formulas, and expert experience.
Provide the diagnostics result. The diagnostics result consists of the static parameter diagnostics result and the parameter modification history within the last seven days.

Usage notes

When you modify the parameters of an RDS instance based on the diagnostics results, you may need to restart the RDS instance for the modifications to take effect. We recommend that you modify the parameters during off-peak hours and make sure that your application is configured to reconnect to the RDS instance.

Note

The parameter diagnostics feature only diagnoses the parameters that can be modified in the ApsaraDB RDS console and provides diagnostics results. The feature does not directly modify parameters. You can modify the parameters in the ApsaraDB RDS console. For more information, see Modify the parameters of an ApsaraDB RDS for MySQL instance.

Billing rules

N/A

Procedure

Go to the Instances page. In the top navigation bar, select the region in which the RDS instance resides. Then, find the RDS instance and click the ID of the instance.
In the left-side navigation pane, choose Autonomy Service > Diagnostics.
Click the Parameter Diagnostics tab to diagnose instance parameters.
- Create a parameter diagnostics task
  Click Analyze to create a parameter diagnostics task. You can view the diagnostics task in the Parameter Diagnostics section.
- View the parameter diagnostics result
  In the Parameter Diagnostics section, find the diagnostics task that you want to view and click Details in the Actions column.
  You can specify a period of time within which you want to view the parameter diagnostics result.
  Note
  - If you want to modify the parameters based on the diagnostics result, click Parameter Settings on the diagnostics result page to go to the ApsaraDB RDS console. For more information, see Modify the parameters of an ApsaraDB RDS for MySQL instance.
  - The following section describes the recommendation levels in the diagnostics result:
    Critical: We recommend that you immediately modify the parameter.
    Warn: We recommend that you modify the parameter based on your business requirements.
    Notice: The value of this parameter is different from that in the default parameter template of the RDS instance.