Linux 7.0's Scheduler Redesign Crushes PostgreSQL Performance, Demands Database Updates

This incident reveals a critical compatibility gap between Linux kernel optimizations and database software, risking significant performance degradation for PostgreSQL users. With Ubuntu 26.04 LTS set to ship Linux 7.0 in April, users face potential production issues unless PostgreSQL adopts the new RSEQ mechanism—shifting responsibility squarely to the database project. The situation illustrates broader tensions in modern systems software where kernel-level changes require coordinated updates across the entire application stack.