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Area

admin/ui

Describe the bug

I'm running Keycloak Benchmark with 30 million users in the database (Aurora PostgreSQL) (edit: all users belong to the same realm).
On the admin UI page, listing the first page of users is fast, independently of the number of users per page, but navigating to the second page is quite slow (28 seconds, see screenshot)

<img width="1905" height="65" alt="Image" src="https://github.com/user-attachments/assets/6325110a-68db-495a-966b-c4d9b6287edb" />

Version

26.4.7

Regression

[ ] The issue is a regression

Expected behavior

A more reasonable response time.

Actual behavior

A very long response time.

How to Reproduce?

Navigate to the user listing page and click on the next page.

Anything else?

Aurora TOP SQL query at the time. It may help track the issue.

<img width="1861" height="207" alt="Image" src="https://github.com/user-attachments/assets/bb7f336d-f444-440a-b0a8-6231a560c196" />

Possible related to https://github.com/keycloak/keycloak/issues/39646, but I'm not using LDAP.