REDLINE
Guides

Performance, explained by the people who measure it

Everything here is written from the measurements Redline takes on real hardware: what the numbers mean, why the same site behaves differently on a phone, and which fixes are worth the engineering time. No listicles, no reposted release notes — each guide is a working method you can follow end to end.

Measurement · 9 min read

How to read a device performance score

What the CPU, memory, layout, GPU and network numbers in a device benchmark actually mean, and how to tell a real problem from normal variance.

Diagnosis · 10 min read

Why your site is fast on your laptop and slow on a phone

The hardware gap, thermal throttling, network variance and cache warmth that make developer machines a misleading place to judge performance.

Optimisation · 11 min read

A practical checklist for fixing slow page loads

An ordered checklist for making a page load faster, with the realistic gain and the cost of each step so you can stop at the right point.

Method · 9 min read

Load testing versus real-device testing

What server-side load tools like k6 and JMeter measure, what they structurally cannot see, and when you need device-side measurement instead.

Metrics · 10 min read

Core Web Vitals in plain English

LCP, INP and CLS explained without jargon: what each one measures, what usually breaks it, and the change that most often moves it.

Measure before you read

Most of these guides are easier to follow with your own numbers in front of you. The stress lab runs in the browser you are holding, takes about five seconds and keeps the results on your device.

Run a stress test