WordPress Performance and Scaling
A complete course in making WordPress 7.0 fast and keeping it fast: measurement, query budgets, caching, Core Web Vitals, infrastructure and load.
- Modules
- 03
- Lessons
- 09
- Reading time
- 4H 45M
- Words
- 19,274
What you will be able to do
- Build a benchmark that produces the same answer twice.
- Find the queries that matter instead of the queries that are numerous.
- Choose between the object cache, transients and a page cache with reasons.
- Fix Core Web Vitals from field data rather than a synthetic score.
- Size PHP workers, cron and the object cache for real traffic.
- Survive a traffic spike without a cache stampede taking the site down.
Before you start
Ability to read PHP and SQL, access to a WordPress install you can modify, and ideally a staging copy you are allowed to break.
Still being written
3 of 6 modules are finished and readable now. The remaining 3 are in progress and will appear here as they are published. Nothing already written is removed, and the lessons below will not change underneath you.
WordPress performance advice is abundant and mostly wrong, because it is given without a measurement. Somebody installs a caching plugin, the site feels faster on their laptop, and a conclusion is drawn. Then a sale starts, the cache misses under concurrency, and the database does exactly what it was always going to do.
This course is written against WordPress 7.0 and WooCommerce 11.2, and its first module is about measurement for a reason: every later claim in the course is something you are expected to verify on your own install. Query budgets, index design and the options table follow, then the three caching layers and the invalidation problem that decides whether caching helps or merely postpones.
The last two modules are about the parts that only appear under load: PHP worker counts, cron and queues, and what actually happens when a popular cache entry expires while thousands of requests are arriving at once.
Curriculum
3 modules, 9 lessons
Measuring first
Benchmarks that repeat, query logging, profiling, and the difference between lab and field data.
3 lessons · 1H 35M
The database
Query budgets, index design, the options table, postmeta against custom tables, and slow query analysis.
3 lessons · 1H 35M
Caching layers
Object cache, page cache, transients, cache keys, and an invalidation strategy you can defend.
3 lessons · 1H 35M
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