The Cost Of JavaScript in 2019

As the world build sites that are more heavily reliant on JavaScript, we sometimes pay for what we send down in ways that we can’t always easily see.

Addy Osmani explains how and why JavaScript is the most expensive resource your site uses today—especially on mobile. Addy also shares tips for fixing JavaScript performance issues so everything loads quicker. A little discipline can help if you want your site to load and be interactive as soon as possible on mobile.

Article: https://v8.dev/blog/cost-of-javascript-2019
Video: https://www.youtube.com/watch?v=X9eRLElSW1c&feature=youtu.be

Slides are from PerfMattersConf 2019: https://www.perfmattersconf.com/talks/#addy

More from Addy on https://addyosmani.com

Transcript

27. addyosmani.com/blog/usability
29. https://philipwalton.com/articles/why-web-developers-need-to-care-about-interactivity/ *
38. YOU SIT ON A THRONE OF LIES
39. * Background compilation: 1-2% improvement to main thread V8 time time reduction. Background parsing and other improvements to parse reduced overall V8 load time by up to 10-20%
48. ~20-40% reduction in parse and compilation time during load.
53. bit.ly/lazy-react-article
54. 125KB main.js
55. 36KB main.js 89KB chunk.js
58. bit.ly/tti-vue