Ok, it's not just Google. It's Amazon and Microsoft and Facebook and eBay. They're all pretty much as bad as each other. But Google are terrible for it.
Cross-domain scripting allows adverts from different sites to be placed inline, in a webpage, as if it were part of the original content. In the dark ages, we used to do something similar in IE, using iframes. Except it wasn't adverts - but the idea was the same; drag some content from another server and make it appear as if it's part of the original document.
At home I have a VirginMedia 100Mbs/sec connection.
It's pretty whizzy. And even allowing for relatively high contention ratio, I average around 70Mbs/sec. So it's not the connection. But when I recently tried to look for floor tiles on eBay (the exterior cladding on the bungalow is coming to and end so we're looking to putting a fancy skirt around the bottom) I kept getting error messages like this:
And having to wait 10-15 seconds, staring at a blank screen (the Chrome browser would go entire white, filling the screen all except for a "not responding" header in the title bar) between page loads. That is, when the page did eventually load.
So Steve suggested PingDom to see what was going wrong.
googletagservices.com, g.doubleclick.net, googlesyndication.com and more. All calls to Google-related domains that were slowing down the page load.
And this screen shot doesn't show everything - there were over 20 "screenfuls" of this shite - all just to get a single item up on the eBay website (not a page of 25 or so search results, but a single item).
And littered throughout the page load, there were loads of failed documents/scripts.
The internet used to be a wonderful, exciting, interesting place, full of fascinating user-generated content. Now it's a quagmire of adverts and cross-domain scripts that are slowing bringing everything to a grinding halt.
Can you please fix it Google?
And then tell Amazon, Facebook et al how you did it.
I feel like I keep investing in new hardware, a better and faster internet connection, improved networking - and yet web pages take longer to load now than they did five years ago. And back then I was moaning about how shit they were and slower than five years previous....