Your question is Debugging Production Performance Bottlenecks. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
Describe the process you follow when debugging a performance bottleneck in a production environment.
Explain how you confirm the issue, assess customer impact, isolate the bottleneck, and choose between immediate mitigation and deeper investigation. Include how you coordinate with engineering and operations stakeholders, communicate status, validate the fix, and prevent recurrence.