Speed up your PHP application without changing a single query.

A few days ago I set out to answer a simple question: how much faster can a PHP app go if you drop a SQL cache in front of MySQL — without touching application code? The answer is below. On a four-table join aggregating revenue by category and region, Readyset served the same result 60x faster than MySQL. And all I did was change a port number.

This post walks through exactly what I did, step by step, so you can reproduce it yourself.

What Is Readyset?

Readyset is a SQL-aware caching engine that speaks the native MySQL wire protocol. Your PHP application connects to it the same way it connects to MySQL — same driver, same queries, same credentials. Underneath, Readyset proxies queries to your upstream database and, for the ones you choose to cache, serves …

It is a classic trap: you spend a week fine-tuning your cache and your database hits only to realize your application is essentially running with the handbrake on. I saw this with my tests: MySQL and Readyset were returning rows in 0.2 ms, but the application throughput remained capped at 40 queries per second (QPS).

The database isn’t the bottleneck, and the cache isn’t the bottleneck. Your application code is simply leaving performance on the table. While running some demos recently, I found that a Node.js service went from 40 QPS to over 6,000 QPS, which is a 150x improvement without changing a single database setting or query plan. Here is a post-mortem of how application-layer bottlenecks can neutralize even the most aggressive infrastructure wins.

The “Fairness” Trap: Event Loop Lag

In Node.js and similar async runtimes we are taught to “be …