AAI Users Unexpectedly Redirected to Login Page Due to CPU Saturation

Products

• Automation Analytics & Intelligence

Issue/Introduction

Users of Automation Analytics & Intelligence (AAI) report being unexpectedly redirected to the login screen shortly after logging in. This behavior may exhibit the following characteristics:

• The session returns to the login screen even while the user is active.
• Initial login attempts may occasionally return an HTTP 500 Internal Server Error.
• A browser HAR capture shows that a valid session still exists (API calls like /users/me return 200 OK immediately after the redirect).
• The issue occurs frequently during specific intervals (e.g., every 4–10 minutes).

Environment

• Product: Automation Analytics & Intelligence (AAI)
• Version: 24.x
• Platform: Red Hat Enterprise Linux (RHEL)

Cause

The redirects are caused by server CPU saturation during the JammerSequence prediction cycle. When AAI processes a very high volume of predicted job runs (e.g., over 1 million simulated runs), the server CPUs can reach 100% utilization with 0% idle capacity.

During these saturation bursts:

1. The JBoss server becomes unable to respond to routine browser API calls within the default timeout period.
2. The AAI frontend application (React UI) interprets a failed or timed-out API call as a session error.
3. The application executes destroySession() and redirects the user to the login page, despite the underlying server session remaining valid.

Resolution

Hardware Adjustment 

Increase the server's CPU count. For environments processing large schedulers (such as AutoSys instances with over 1 million predicted runs), a 4-CPU configuration is often insufficient. Upgrading to 8 or 16 CPUs provides the necessary headroom to handle prediction bursts while maintaining responsiveness for user API calls.