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Database Workshop

Observation and diagnosis

Spatial analysis management

The Database Workshop (DBW) provides spatial analysis functionality, allowing you to visually view the space usage of an instance, such as table space usage.

Prerequisites

An instance for RDS for MySQL has been created, and the instance status is running. For detailed steps, see Creating an instance.

If the target instance has security control enabled, you need to apply for operation and maintenance read-only or read/write permissions for the current account. For more information, refer to Enabling instance security control (RDS for MySQL), and Applying for operation permissions (RDS for MySQL).

Precautions

The tablespace data is calculated based on the system database information_schema.tables and may be slightly inaccurate. Please refer to the actual values for confirmation.

Instance-level analysis limit: Space usage is analyzed for up to the first 20,000 tables per database instance.

Database-level analysis limit: For a single database (DB), tablespace usage is analyzed for up to 2,000 tables within it.

While using the spatial analysis feature, avoid modifying instance configurations, as this may prevent normal display of space usage.

Advantages

Space analysis can transform complex storage issues into intuitive data views, helping to shift from reactive emergency handling to proactive management.

Global visualization: Charts display key metrics such as used space, space distribution (e.g., data, binlog, undo log), and estimated days of remaining available storage, enabling a comprehensive, at-a-glance view of storage status.

Strong alerting capability: Automatically estimates the number of days until storage is exhausted, proactively identifying potential risks—such as an impending disk full condition—to prevent service disruption.

Deep table-level space insights: Enables viewing key metrics for each table—including tablespace size, fragmentation ratio, and row count—to accurately identify large tables or those with high fragmentation.

Historical trend tracking: Provides space usage trend charts to help analyze growth patterns and forecast future capacity requirements.

Multi-dimensional breakdown: Categorizes and analyzes storage usage across user data, system space, log files (e.g., binlog, undo log), and temporary files to help identify the sources of resource consumption.

Applicable scenarios

Storage scaling assessment: Review current space usage and estimated days of remaining capacity to determine whether immediate scaling is required; combine this with trend charts to forecast future growth.

Performance optimization diagnostics: Analyze tables with high fragmentation and execute ALTER TABLE ... ENGINE=InnoDB or perform a table rebuild to reduce fragmentation and enhance query performance.

Log management optimization: Review the storage占比 of Binlog and Redo Log; if their proportion is excessively high, consider adjusting retention policies—for example, by setting expire_logs_days.

Large table identification and archiving: Sort tables by tablespace size to identify those consuming the most storage, and evaluate whether sharding, partitioning, or archiving historical data is necessary.

Capacity planning and budget control: Leverage space usage trends and consumption statistics to provide data-driven support for resource procurement and budget allocation.

Troubleshooting assistance: When encountering disk read-only or write failures, quickly determine whether the issue is caused by data bloat or log accumulation.

Procedure

Log on to the DBW console.

On the top menu bar, select the project and region.

On the left navigation bar, select Operation and maintenance management > Observation and diagnosis.

On the Observation and diagnosis page, click Space usage.

In the upper left corner of the Space usage tab, switch the instance.

tip

You can also switch to the target instance by searching for the instance ID.

When you access the Space usage tab through Observation and diagnosis on the left navigation bar, information about the first instance in the Instance list is displayed by default.

On the Space usage tab, you can view the following information:

View spatial profile

View trends in space

Create space analysis task

In the Spatial profile section, you can view the Used space, Space usage, and Remaining available days for the current instance.

tip

Space usage includes the occupied space and Remaining space of User data, System, Bin Log, Redo Log, Undo Log, Relay logs, Audit log, Slow log, Error log, Temporary file, and Other documents.

Create space analysis task

Click Analyze now and select the analysis scope in the dialog box:

Analyze all space: Select All space and click OK.

Analyze specified space: Select Specified space, check the target databases and tables as needed, and click OK.

You can select multiple databases simultaneously for analysis. However, when multiple databases are selected, table filtering is not supported.

View space analysis results

You can filter analysis tasks by generation time range. By default, tasks from the past day are displayed, with a maximum history of 30 days.

View task list: Displays an overview of all analysis tasks, including task type, target object, creation time, completion time, state, and error message.

View task details: In the task list, click View details in the Actions column of the target task to go to its space analysis page. Here, you can view the Used space, Space usage, and Tablespace information for the specified space.

In the Tablespace section, you can analyze the detailed storage space usage of tables within all or specified databases and tables in a database instance. This analysis is generated based on statistics from the system database information_schema.tables. This section enables rapid identification of large tables, tables with severe fragmentation, or potential optimization targets, facilitating storage optimization, performance tuning, and resource planning.

The data is sourced from system tables and may contain slight inaccuracies.

To ensure performance, the system imposes limits on the analysis scope:

Instance-level analysis limit: Space capacity is analyzed for up to the first 20,000 tables per database instance.

Database-level analysis limit: For a single database (DB), tablespace usage is analyzed for up to 2,000 tables within it.

In the left panel of the tablespace section, click a database name to switch and view detailed tablespace information for that database. You can also filter databases by entering the database name in the search box. The specific details displayed include:

Parameter	Description
Table name	Table name in the database.
Storage engine	The storage engine used by the table.
Tablespace	The total space occupied by the table (including both data and indexes), displayed in MB or KiB.
Tablespace ratio	Indicates the proportion of space that this table occupies within the current database, sourced from information_schema.tables, making it easier to identify large tables. The calculation method is: Single table's (INDEX_LENGTH + DATA_LENGTH + DATA_FREE) / total tables' (INDEX_LENGTH + DATA_LENGTH + DATA_FREE).
Data space	The size of space storing actual data, taken from the DATA_LENGTH field in information_schema.tables.
Index space	The physical storage size of the index structures, sourced from the INDEX_LENGTH field in information_schema.tables.
Fragmentation ratio	The proportion of tablespace that is not effectively utilized—higher values indicate a greater need for optimization (e.g., optimize table). This metric is sourced from information_schema.tables. The calculation method is: DATA_FREE / (INDEX_LENGTH + DATA_LENGTH + DATA_FREE).
Number of table rows	The total number of rows (records) in the current table.
Average row length	The average number of bytes per row, reflecting data density.
Auto-increment ID value.	The current maximum value of the auto-increment column, useful for assessing growth trends, sourced from the AUTO_INCREMENT field in information_schema.tables.

Last updated: 2026.08.04 11:16:29