How to Configure a ThreadPool to Send 10 Million SMS in One Hour (Java)
The article walks through calculating the required QPS for 10 million SMS in an hour, derives a precise ThreadPoolExecutor configuration (core 200, max 500, queue 5000, 60 s keep‑alive, CallerRunsPolicy), and provides complete Spring Boot code with production tips such as pagination, retry, idempotency and rate‑limiting.
