Friday, April 1, 2005 Google engineer Reza Behforooz announced in a Google blog entry on March 30 that search engine Google has enabled “link prefetching” for some of their search results. The link prefetching has not been standardized, but it can enable faster page loading of Google search results in Mozilla and Firefox browsers that have the feature enabled.

When Google determines a user has a high likelihood of clicking on a search result, Google inserts a tag into the results they send out in response to a search. Some browsers can then preload that page, so in the event the user does select the page, it loads very quickly.

For example, a Google search for “wikipedia” today by Pingswept yielded an HTML page with this code included:

<link rel="prefetch" href="http://en.wikipedia.org/wiki/Main_Page">

While not a formal benchmark, in casual testing by Pingswept, Firefox 1.0.2 loaded the Wikipedia main page in about half the time when the page had been link prefetched, as opposed to when it had not been. The load times were approximately 1.5 seconds and 3 seconds respectively. Internet Explorer 6.0 loaded the same page in slightly less than 3 seconds.

Users who want to disable prefetching in Firefox can do the following:

  1. Type “about:config” in the address bar.
  2. Scroll down to the setting “network.prefetch-next”.
  3. Right-click on the value and click “Toggle”.