News New Intel Macs fail speed test

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dipdude

Forerunner
Performance for the new Intel powered Mac computers is far less than the company promised during last week's unveiling.

The Macworld trade publication put the new Intel iMac to the test against an old G5 model and found that the speed gains fell short of the promised results by a significant margin.

Apple chief executive Steve Jobs last week at the MacWorld tradeshow boasted that the new iMac would get at least a 200 per cent performance boost over a previous generation G5 system.

"What different is that the new iMac [with the] Intel processor is two to three times faster than the iMac G5," Jobs promised delegates.

Apple based its findings on two benchmark studies where systems are tested in a controlled environment. Such tests however fail to reflect performance in real world applications, the publication pointed out.

Performing a series of everyday tasks with software specially designed for the new Intel Mac systems, the new Mac machines showed an average performance increase of 10 to 25 per cent. In a few cases the new systems showed an improvement of roughly 80 per cent, but those couldn't be solely contributed to the new processor.

Software developers have to recompile and recertify their applications to run on the new Intel Macs. While Apple has finished this process for OS X and the iLife suite of products, many third party software titles including Photoshop and Microsoft Office have yet to be moved over. Allowing customers to use their old software, Apple has developed the Rosetta emulator.

The Rosetta application translates instructions for a G5 processor into a language that the new Intel chips understand. While this is typically a compute intensive task, Jobs has previously promised that: "most users will not even know that [Rosetta] is running."

The Macworld test found that performance dropped by more than 50 per cent for applications running on Rosetta. While such a decrease might be acceptable in Office, users are likely to get frustrated when they try and use more demanding software such as Photoshop.
 
Rosetta is an emulator. An emulator is an emulator is an emulator is an emulator.

To quote from Arstechnica:

How it works

When an application launches, the system looks to see if it's a Universal Binary. If not, the application is launched using Rosetta. Rosetta runs in the same thread as the application, and translates blocks of code as they come up. The translated code is then optimized, and is cached for reuse. So if an application is reusing the same piece of code, you will see a performance benefit, since the translation needs only occur once.

When Rosetta was announced, there was a lot of speculation over how well it would work. In a news post from August 2005, Hannibal wondered if it would be "usable, mostly usable, or barely usable." I'm here to tell you it's usable.

As Hannibal pointed out, Rosetta has a few advantages that earlier translation and emulation technologies lacked. First and foremost is an extra processor core. In addition, it's integrated into the operating system, so there's no need to emulate drivers. Graphics and UI elements do redraw quickly.

Overall, I'm very impressed with Rosetta. Aside from Unreal Tournament 2K4, I've not run into a single application that was unusable on the iMac. Some were definitely slower on the Core Duo iMac than on the iMac G5. Launching typically took a bit longer, and I would usually get the dreaded spinning beachball for a couple of seconds once the application launched. Afterwards, it was smooth going.

Some tasks like Photoshop filters were definitely slower going on the Core Duo iMac than on the iMac G5. But using applications such as Microsoft Office felt so smooth that I really didn't get the feeling that there was some sort of translation at work.

For the most part, Rosetta should be more than adequate when it comes to general-purpose office apps, but for the heavy-duty stuff like Photoshop and other CPU-intensive applications, you'll notice a slowdown. Some reportedly won't launch at all, like Final Cut Pro 5 and Logic 7. I tried launching FCP 4.5 and it wouldn't run, saying that I needed an AGP card. I tried to tell it that PCIe video cards are much better, but it wouldn't listen. DVD Studio Pro 2.0.3 launched, and seemed to run fine, albeit slowly.
Click to expand...

In any case, Rosetta is only supposed to be a temporary relief until heavy applications such as Photoshop and the like are rewritten. Which they VERY MUCH will be.
 
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