PostgreSQL and Linux Memory Management

As a DBA # 2023 was a year of comprehensive PostgreSQL learning for me, and 2024 has been a year of comprehensive PostgreSQL operations. There’s actually a lot of material I really want to dive into but haven’t had the time. This year was mainly case analysis — I could only supplement my foundational knowledge here and there. Mid-year there was a discussion about “will DBAs be eliminated in the cloud era.” This discussion left a deep impression on me. I thought about many things afterward — why do others seem to have so few things to deal with while I, as a DBA, have so much? I even went into cloud computing groups to debate about it, and I actually gained something from it. Different perspectives lead to unexpected conclusions. The conclusion of the debate may boil down to just one thing: DBAs are providing emotional support to their leaders.

This article focuses on common PostgreSQL operations issues — rare edge cases that surface once every two or three years are out of scope. It’s primarily a technical ops summary, aiming for clarity and quick applicability. Deep dives at the source-code level are deliberately avoided. SQL Performance & Execution Plans # Sudden Execution Plan Changes # PostgreSQL does not support optimizer hints natively, and the community has made it clear it never will. The PG community’s stance is roughly: “Our optimizer is perfect. If the current plan isn’t good enough, it’s because the developer doesn’t understand optimization.”