Suppose you need to create a replica for a 1 TiB database. You have a fast server with NVMe storage and 75 Gbps network, but pg_basebackup typically delivers only 300-500 MiB/s due to its single-threaded architecture — regardless of how powerful your hardware is (though PG18 brings a surprise we'll discuss later).
The solution: replace pg_basebackup with pgBackRest and leverage parallel processing to achieve significantly faster replica creation, saturating (≈97% of) line rate on a 75 Gbps link.
Note: This is an R&D-style exploration focused on performance benchmarking on idle systems, not a production-ready automation guide. Many considerations important for production environments (monitoring, retry logic, integration with orchestration tools, etc.) are intentionally omitted to focus on the core performance characteristics.