Design a high-level system architecture for a global real-time bidding platform that must handle 100,000 requests per second with latency under 100ms. Address the following concerns: data consistency across geographic regions, handling of network partitions, fault tolerance, and auto-scaling strategies. Describe the choice of database technologies (SQL vs NoSQL), message brokers, and caching layers. Create a detailed diagram description explaining the data flow from the user request to the database persistence layer.