Performance optimization Intro
Measure before you fix: the first thirty minutes
Optimising by intuition usually improves something. The trouble is that it was rarely the bottleneck. Start by splitting the request into segments and getting numbers.
Technote
Profiling WordPress performance
Turning "it feels slow" into numbers — finding which queries and hooks spend the time, and stacking cache layers in the right order.
4 articles
Performance optimization Intro
Reading a query profile: slow versus duplicated
They sit side by side in the same panel but they are not the same problem. One needs the query rewritten; the other disappears with a cache. Telling…
Performance optimization Practical
The N+1 problem: get_post_meta in a loop, and priming
WP_Query primes caches for its own results only. A hand-built list of IDs gets none of that for free — and that difference decides your query count.
Performance optimization Practical
The object cache: what Redis actually removes
Repeated identical lookups disappear. One slow query does not. Miss that distinction and you will wire up Redis and then ask why nothing got faster.