Your question is Parallel Programming and Scaling. 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).
Tell me about a real-life software engineering scenario involving parallel programming, scaling, and caching.
Describe a concrete system you worked on, including the workload, why parallelism was needed, how the system scaled, and where caching fit into the design. Explain the tradeoffs, bottlenecks, correctness concerns, and how you measured success. Be prepared to discuss what failed, how you diagnosed it, and what you would change in a redesign.