Remove articles vitals-measurement-getting-started
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In Defence of DOM­Content­Loaded

CSS Wizardry

Honestly, I started writing this article, for no real reason and somewhat without context, in December 2022—over half a year ago! TTFB is a good measure of your server response times and general back-end health, and issues here may have knock-on effects later down the line (namely with Largest Contentful Paint). View unabridged.

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Measure What You Impact, Not What You Influence

CSS Wizardry

A thing I see developers do time and time again is make performance-facing changes to their sites and apps, but mistakes in how they measure them often lead to incorrect conclusions about the effectiveness of that work. Problems When Measuring Performance. However, in a sentence: Measure what you impact, not what you influence.

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Optimising Largest Contentful Paint

CSS Wizardry

link] [link] --> Largest Contentful Paint (LCP) is my favourite Core Web Vital. It’s the easiest to optimise, and it’s the only one of the three that works the exact same in the lab as it does in the field (don’t even get me started on this…). Let’s start with the easy stuff. LCP is a milestone timing—it measures….

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Improving Core Web Vitals, A Smashing Magazine Case Study

Smashing Magazine

Improving Core Web Vitals, A Smashing Magazine Case Study. Improving Core Web Vitals, A Smashing Magazine Case Study. Why are my Core Web Vitals failing?” It all started with a series of tweets last March with a cry for help : Smashing Magazine’s tweet asking for help. Barry Pollard. 2021-12-20T05:30:00+00:00.

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All of Netflix’s HDR video streaming is now dynamically optimized

The Netflix TechBlog

We were, however, missing the systematic ability to measure perceptual quality ( VMAF ) of HDR streams since VMAF was limited to standard dynamic range (SDR) video signals. A vital aspect of such development is subjective testing with HDR encodes in order to generate training data. By June 2023 the entire HDR catalog was optimized.

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Understanding the performance impact of anti-flicker snippets

Speed Curve

But this practice comes with some performance measurement pitfalls: Hiding the contents of the page can have a dramatic effect on the Web Vitals that measure visual experience, such as First Contentful Paint (FCP) and Largest Contentful Paint (LCP). Effects on other Web Vitals. Hiding the page contents.

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Farewell FID. and hello Interaction to Next Paint!

Speed Curve

INP will replace First Input Delay (FID) as a Core Web Vital in March of 2024. It's been three years since the Core Web Vitals initiative was kicked off in May 2020. While we definitely get excited about emerging metrics, we also approach each new metric with an analytical eye. When should you start caring about INP?

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