Perhaps the most practical "page 20" wisdom concerns the . The default fetch size for most drivers is 10. This means that to read a result set of 10,000 rows, the JDBC driver makes 1,000 round-trips to the database. In a high-latency network environment (e.g., microservices communicating across regions), this is a death sentence.
High performance starts with resource acquisition. Using HikariCP (the fastest pool) over a default pool can increase throughput by 50%. The "20 microsecond" validation query rule is key. high-performance java persistence pdf 20