Yale College registration system resilience testing

In April 2021, Yale College launched a new registration system and pivoted to an earlier calendar for registration. Since that release, when Yale College registration opens each term, students take thousands of real-time actions that directly hit the student systems database. The fall 2022 add/drop window produced the most sustained period of database load to date. Concurrent with the fall add/drop opening, the Graduate School’s registration project was finalizing testing and planning to bring their registration process into a more modern, accessible system and align their registration timeline with Yale College for the spring cycle. With thousands of additional students expected to register at the same time the next term, the team (including representatives from the University Registrar’s Office, as well as the Student & Academic Support Systems and Platform Engineering teams) prioritized efforts to ensure that future registration windows would be stable and predictable for applications across all the schools.

Improving performance was truly a cross-team accomplishment; efforts to stabilize the system included functional changes to processes and system changes. Crucially, the team invested in a phased approach to performance testing, working with Yale’s QA and Platform Engineering teams. The team tuned the system in a series of small-scale tests throughout the fall, ramping up to a full day of dedicated performance testing incorporating multiple registration systems. During the tests, thousands of registration attempts were simulated, and the team tuned performance systematically, resetting the tests and measuring the results of each change. The group was able to add in test students from different schools and address load concerns across multiple applications.

When spring add/drop opened for Yale College and the Graduate School in January, the value of the performance tuning was evident. The systems logged their strongest performance yet, with the database load remaining well within safe margins for the entire registration cycle. In addition to stabilizing the system, the improved performance positively impacted the user experience as registrations were processed faster and students received confirmation of course registrations quicker than ever before.