It’s come to my attention that prefetching with the Firefox extension Fasterfox could be bad and causing extra strain on yours, and other peoples, webserver and possibly pocketbook!

Fasterfox, in essence, is a prefetcher. It reads the page you are currently browsing and attempts to download all of the other pages being linked to. When you do decide to click on a link on the page, the browser can the load that page from disk rather than fetch it from the Internet. It then starts the whole process again – downloading links from the new page into the cache ready for the next page to be clicked on, etc…

It’s bad for your ISP (but that’s between you and your ISP).

It’s also bad for website owners – who will see their traffic increase exponentially. That could lead to them exceeding their bandwidth quotas without any benefit, as few of those downloaded pages will ever be looked at by a human being.

And it’s bad for the Internet as a whole – what would happen if everyone used this plug-in? The additional load on our ISPs, the additional load on webservers and the additional load on the transit links that do all the hard work in between would noticeably slow down the Internet experience.

Read much more over at Ben Metcalfe’s Blog.

To make it really hit home, lets say you are using the Fasterfox extension and you have prefetching on (by default it is). Every time you visit your website, you could be causing your bandwidth to increase more than 10 times the normal amount! If you go over your bandwidth, won’t your host shut down your site or charge you more money?

Now I’m not saying don’t use Fasterfox, I’m saying go into your preferences (or options on Windows), click on Fasterfox, click on the custom option then go to the Fasterfox tab and turn Fasterfox Enhanced Prefetching off.

Now the Fasterfox site has slightly different views, but they don’t totally disagree with what is being said. Judge for yourself and make your own decision. I turned prefetching off and I encourage others to do so too.