> JavaScript must be downloaded, then run through a JIT compiler (even if you don’t use it), and then executed, and all this must be done before any of the JavaScript can start rendering the UI. This introduces a lot of delay before users can see the UI, especially on low-end devices.
> There is some correlation between the [Lighthouse] Performance Score and how well your site will do for real users. Still, lab testing alone doesn’t capture all speed issues (similarly, field testing might prove inadequate in showcasing other speed problems). That’s why relying on Performance Score is not a bulletproof strategy. We…
It's heartening to see how many media sites in @speedcurve's Page Speed Benchmarks have sub-2.5s LCP times!
For some of the sites with poorer LCP, perceived #webperf / #ux isn't the issue. They're fast to start render. The main culprit is that the LCP element is just wrong.
The takeaway: don't just look at the numbers for your metrics. Visually validate them to make sure they're measuring the right things!
🟡 Delivering a fast UX to your users
🟢 Knowing the minute your site speed starts to suffer (including metrics like Core Web Vitals)
🔵 Fixing performance issues FAST
> JavaScript must be downloaded, then run through a JIT compiler (even if you don’t use it), and then executed, and all this must be done before any of the JavaScript can start rendering the UI. This introduces a lot of delay before users can see the UI, especially on low-end devices.
> Interaction to Next Paint (INP) is a Core Web Vital that measures how responsive a page is to interactions. Due to INP's scope, it can be difficult to identify why some interactions are slow. Learn how to use new Chrome APIs that provide detailed information on the causes behind slow interactions, and how to collect insights from your website's…
One of the teams I've been working with to climb the performance management maturity ladder is...Edge!?!
We build a lot of the browser out of web "stuff" these days (think bookmarks, history, downloads, settings, new-tab-page, etc.), and moving away from React to a modern Web Components + HTML-first architecture has had a huge benefit for users, particularly folks on low-end hardware:
Cookie consent popups and banners are everywhere, and they're silently hurting the speed and UX of your pages. Learn the most common problems – and solutions – with measuring web performance with a content manager platforms (CMP) in place.
If you're considering coming you can get 10% off with the code 'Friends10', making the price just ~£140 ex VAT. Student tickets are also available for £60 – exceptional value! Full details 👉 https://pixelpioneers.co/
Finally got myself a ‘new’ phone today, it’s an absolute banger.
No, it’s not an iPhone 15 Pro Max, it’s a Samsung A51 for #webperf testing and it scores less than half an iPhone 7 on Geekbench 😬 you can feel the input lag even during device setup!
While on the topic of Skating: I recently rewatched (and then read an unspeakable amount of bio on) Rodney Mullen's 2014 Velocity Conf talk in Santa Clara about Failure, Learning & disconnecting the Ego: https://www.youtube.com/watch?v=RiSiY9iWrMU
I can almost not believe what a privilege it was to see him there live 10(!) years ago. And furthermore, how ignorant I was back then what an incredible treat John Allspaw gave us #WebPerf geeks with this.
PERFORMANCE HERO • per-FAWR-muhns HEER-oh • A person who's made a huge contribution to the #webperf and #ux community, without whom the web would be a sadder, slower place.
Celebrating this month's @speedcurve Performance Hero, Estela Franco (@guaca)!
> Interaction to Next Paint (INP) is a Core Web Vital that measures how responsive a page is to interactions. Due to INP's scope, it can be difficult to identify why some interactions are slow. Learn how to use new Chrome APIs that provide detailed information on the causes behind slow interactions, and how to collect insights from your website's…
🟦 RUM INP attribution & subparts, including dimension filters (e.g. browser, connection type)
🟦 RUM update: lux.js v314
🟦 New synthetic test scripts
🟦 Upgraded test browsers for Industry Benchmarks