Performance tuning
Everything we have written on this subject, newest first.
MySQL Performance at Scale
MySQL still powers a large share of the world's production databases, particularly in e-commerce, SaaS, and applications built on the LAMP stack. But the performance challenges that emerge at scale are often different from what teams expect, and the tooling to diagnose them has improved significantly in recent years.
Read morePostgreSQL Performance Tuning
PostgreSQL tuning advice tends to start and end with shared_buffers. That's table stakes. The real leverage for teams running PostgreSQL at scale is in vacuum tuning, query plan observability, and the performance improvements in PostgreSQL 17 that many teams haven't adopted yet.
Read moreWhy do we still trust metrics that lie to us?
Teams celebrate 99% cache hit ratios while their databases burn. The metric looks perfect, but the queries are reading 50x more data than needed. A problem first described in 2004 that we still haven't solved.
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