If you haven’t noticed already, both Lara Callender Hogan and Ilya Grigorik have released their books on web performance for free. Free as in read-on-the-web, not as in ebook or print, of course. Both Lara and Ilya originally released their books with the publisher O’Reilly Media, also known as “you know, the animal book’s” according to some of my friends.
Both Lara Callender Hogan and Ilya Grigorik is credible when talking web performance optimization. Lara’s book, which I enjoyed from cover to cover, is introducing a lot of great concepts. One of the memorably things is when she explained how her employer, Etsy, evaluated how images related to the bounce rate of visitors. They found out that 160 Kb of images increased the bounce rate with an alarming 12 %.
Introduction on web performance
Lara’s book is a great introduction for noobs on web performance optimization, or maybe if you’re trying to speed up your intranet. When ready to make your next leap, perhaps Ilya’s more technical perspective seems logical.
Ilya is working as an performance advocate on Google- He also is participating in a lot of great podcasts – for instance, talking about HTTP/2 on The Changelog podcast. Ilya’s specialty is networking on the web, or according to some, the infrastructure or architecture of the Web.
When I introduce the subject of web performance in the book Web Strategy for Everyone, it goes like this:
“When downtown in Gothenburg, I had 16 Mbit / second downstream and 3 Mbit / second upstream with a delay of 0.048 seconds. In a cabin, out in the woods in Fengersfors, there was however a bit more modest 0.035 Mbit / second downstream and 0.4 Mbit / second upstream, with a delay of a full 1.2 seconds!
Let us calculate a little how this might affect a visitor on a little too obese responsive website at 5 MB divided into 30 different files – a weight many Swedish municipalities deemed suitable with their fine responsive homepages. With the fast connection example from earlier, such a website takes about 1.4 seconds of delay plus 3.2 seconds to download. For an abnormally heavy webpage, it is quite ok that it is loaded in under 5 seconds. The same material sent through the slow connection example though instead takes 35.8 seconds of delay and 143 seconds to download. That is almost three minutes!”
At the moment I’m at the cabin in Fengersfors. But for the moment on a wifi, connected to a brand new fiber to the Swedish Internet backbone. But tomorrow, I’ll be on my mountainbike out in the woods. I’d better not need connectivity to the cellular network all of the time during my exercise – there are lots of skip zones along my route.