Act as a Senior Solutions Architect. Design a microservices architecture for a global payment processing system capable of handling 100,000 transactions per second. Your design must address eventual consistency, idempotency in distributed transactions, and circuit breaker patterns for fault tolerance. Explain how you would handle database per service versus shared database challenges, and detail your strategy for inter-service communication (synchronous vs. asynchronous). Include a breakdown of the infrastructure components required for deployment.