bumpski - 4:51 pm on Apr 6, 2007 (gmt 0)

As a webmaster that is always trying to boost website performance, I'm disappointed to see an image file be loaded where in the past there was simply text. I'm spending a lot of time shaving milliseconds off page load time and now Google shoves in another image to fetch from it's already somewhat slow [pagead2.googlesyndication.com...] server. To Google's credit they do provide GZIP compression on almost all file types (many, many websites amazingly do not), but this does nothing for already compressed image files.

With multiple ad units, ad content fetches, javascript fetches and javascript fetches from cache ( which does take up rendering time ), Google's ads are the single largest time penalty for page loads on many high performance sites. This new "Ads by Google" [pagead2.googlesyndication.com]
image is a 2kb additional fetch. It appears that at least Google has made sure this is the last fetch made to the pagead2 domain so it does not block other fetches, such as the more important ad content.

There was a time when the ads worked well in an IFrame, allowing complete decoupling of the load time, but this IFrame capability has long since been partially broken. Placing the ad's code at the end of the page helps but there can be so many fetches to the one server it blocks all other asynchronous browser activity for many milliseconds. Google's ads cannot be made to execute "fully" asynchronously without using an IFrame.

This new "Ads by Google" format could be handled fairly well, simply with fonts, classes, and styles, but of course Google wouldn't have absolute control of the look.