Managing Cache in the SQL Storage of the Reporting REST Service

Environment

Product

Reporting

Description

I encountered an issue where the cache in Telerik Reporting is not clearing automatically, causing certain database tables(e.g. tr_String, tr_Object) to grow indefinitely.

Each report generated is unique, so caching doesn't provide much benefit in this setup. I need to either prevent caching entirely or ensure the cache is cleared to prevent database growth.

Solution

The Reporting REST Service will always periodically trigger cache clean-ups. However, depending on how the service is used, the conditions required for a given asset to be considered expired in the cache may need more time to be met. We advise looking into the Telerik Reporting REST Service Storage Revealed blog post for more details on the topic.

With that being said, in the sections below, we will share some of the recommended approaches for clearing the storage more often.

Adjusting the ClientSessionTimeout Property

Use the ClientSessionTimeout property to control the session expiration time. The default value is 15 minutes.

• Avoid setting it to zero, as this causes sessions to expire immediately, leading to errors like "410 Gone" when rendering reports.
• Use a reasonable timeout value to balance performance and user experience.

Manual Cache Cleanup

To manually clear cache data, use SQL queries during maintenance windows or off-peak hours.

For example, execute the following query to identify and remove cache records based on a specific date threshold from the tr_Oject and tr_String tables. Start with a SELECT query to verify the results before running a DELETE.

SQL Query Example

sql

SELECT TOP (1000) o.[Id], o.[Value]
FROM [RESTDB].[dbo].[tr_Object] o
INNER JOIN [RESTDB].[dbo].[tr_String] s
    ON LEFT(o.[Id], CHARINDEX('\', o.[Id], CHARINDEX('\', o.[Id]) + 1) - 1)
     = LEFT(s.[Id], CHARINDEX('\', s.[Id], CHARINDEX('\', s.[Id]) + 1) - 1)
WHERE s.[Id] LIKE '%\%\LCT'
  AND s.[Value] < '2026-01-01';

• Replace '2026-01-01' with an appropriate threshold date.
• After verifying the results, replace SELECT with DELETE to remove the records.

Additional Considerations

• Run manual cleanup during scheduled maintenance or off-peak hours to minimize disruptions.
• Ensure the Reporting REST Service is active for automatic cache cleanup to function correctly.

See Also

• Report Viewer and Reporting REST Services Cache Management
• Telerik Reporting REST Service Storage Revealed