Preparing for Black Friday Scale: k6 Load Testing, PgBouncer Pooling, and Virtual Waiting Rooms

E-commerce outages during shopping holidays stem from untested concurrency ceilings, database connection exhaustion, and cold caches crashing under sudden initial traffic waves.

A production k6 scenario ramps from 1,000 to 25,000 concurrent virtual users across catalog navigation, product detail loading, and atomic cart reservations.

PgBouncer transaction pooling prevents PostgreSQL process bloat, while edge-based Virtual Waiting Rooms queue excess demand gracefully during historic traffic peaks.