☕ Welcome to The Coder Cafe! On April 3, 2026, Salvatore Dipietro, an engineer at AWS, posted a patch to the Linux kernel mailing list. The reason: on a 96-vCPU Graviton4 machine running Linux 7.0, PostgreSQL throughput had dropped to roughly half of what it produced on Linux 6.x. In this post, we will trace what changed in Linux 7.0, how PostgreSQL manages memory, and what role memory pages ...