Firefox 3.0 Beta 4 users are reporting that Mozilla's new browser is dramatically faster than its predecessor – as well as faster than the latest versions of Internet Explorer, Opera and Safari.
Mozilla's chief developer said the speed increase is the result of hundreds of performance improvements designed to make the open-source browser the best at running complex Web 2.0 applications.
"We've been working on performance for a long time," said Mike Schroepfer, Mozilla's vice president of engineering. "Each beta of Firefox 3.0 got better. Beta 1 was better than Firefox 2.0, Beta 2 was better than Beta 1 and so on. Some of the big architectural changes [we've made] had begun paying off. Now we're at the point where we can turn the knob to get it to perform well."
With Firefox 3.0 Beta 4 just released this week, users and bloggers have already put the browser through its paces and published the results of head-to-head benchmark tests between Firefox, Opera, Apple's Safari and Microsoft's Internet Explorer.
Schroepfer, however, refused to be drawn into a conversation about benchmarks. Instead, he talked about what the open-source project is looking to do.
"There are lots of ways to 'game' the system [in benchmarks], but what we're trying to do is speed up the things that enable people to run the really heavy-duty applications on the web.
"Web apps today are magnitudes more complex than those from five years ago. When Yahoo started out, it wasn't anything more than a bullet list. Now it has widgets and word processing. It's important for us to make it possible for web designers to create complex applications. They can be confident building [big web applications] knowing that Firefox can handle them."
Firefox's developers have dealt with hundreds of performance-related bugs and changes, Schroepfer said. "There are a bunch of things that have to come together to get these kind of results," he said, as he ticked off several. "We optimised JPG encoding, developers took advantage of more and newer compiler options and we found a way on Mac OS X to keep it from throttling page rendering."
Boosting Firefox's performance for the mobile market is also important, Schroepfer said. "The performance gains carry over into mobile, where underpowered devices are the rule," he said. "It should really help us there."
Mozilla is at the end of the line in the mobile space. There, Opera Mobile leads all others in popularity on handsets. IE, on Windows Mobile-powered smartphones, and Safari, on the iPhone, are also ahead of Firefox.