Flash sale load shedding

Design load-shedding and graceful degradation for an e-commerce site during a flash sale that drives 20x normal traffic. The checkout/payment path must stay up even if it means dropping non-essential features (recommendations, reviews, analytics). The system must shed load before it collapses, prioritizing revenue-critical requests. Design how you classify, prioritize, and shed traffic, and how you decide when to start shedding.