Some Legacy Subsystems Wont Get Windows 64-Bit Support

By Peter Galli  |  Posted 2004-05-05

Some Legacy Subsystems Wont Get Windows 64-Bit Support

SEATTLE—While Microsofts upcoming Windows 64-bit client for extended systems will be almost feature-compatible with Windows XP Professional, some legacy subsystems and transport protocols will not be supported in that release.

"Not included in 64-bit Windows are some legacy subsystems like 16-bit support, the OS/2 subsystem and the portable operating-system interface for Unix [Posix]. Some of the legacy transport protocols will also be lost," Brian Marr, product manager for the Windows 64-bit client, said Wednesday at a session on 64-bit computing during the Windows Hardware Engineering Conference (WinHEC) here.

In March 2003, Microsoft released Windows XP 64-Bit Edition, which supported the Itanium processor family. The next version of the product for 64-bit x86 extensions will be released in the fourth quarter of this year, and it will give users the ability to run their 32-bit applications today and then move to 64-bit computing down the road, he said.

On the server side, Microsoft is focusing on Windows Server 2003 Service Pack 1 (SP1), which is due by the end of the year. A number of its 64-bit Windows Server ports will be made available simultaneously with SP1. These include Windows Server 2003 Standard Edition for Intels 64-bit Extended and Itanium processors and Windows Server 2003 Extended Edition for AMD 64-bit Extended processors.

The industry has a huge opportunity with 64-bit computing, but Microsoft cannot do it alone, Marr said, repeating the calls by chief software architect Bill Gates and Jim Allchin, Microsofts group vice president of platforms, for developers to write 64-bit drivers.

"The biggest thing about moving to 64-bit computing is that 32-bit drivers wont work, and we really need the ecosystem around that to make this work," Marr said. "Microsoft can provide the foundation work, but without you and our partners, we cannot achieve this. We are looking to you to help us provide drivers for 64-bit."

Next Page: We see this as the default platform on PCs in the next few years, Marr says.

New Default Platform


Moving a 32-bit driver to 64-bit Windows and the port around this "is the easy part, but the work comes in the testing," Marr added. "My understanding is that the driver port is pretty painless. I would also say that by the end of summer, you can safely port your drivers over.

"The architecture that you need to support your application should be in the product, and if it is not, let me know and I will chase this down," he said.

The upcoming 64-bit extension release will have English and Japanese versions off the bat, followed by German, Spanish and Swedish versions, with the server expected to follow the same path. "We expect this release to be more broadly adopted than we were first hoping," Marr said.

"CPU and memory limits are the compelling factors of this operating system, which is now capable of supporting up to 16 terabytes, but as memory grows we will be able to test greater amounts of memory and then build this into the product."

Microsoft says Palladium, its next-generation secure computing base, is still kicking and will debut in Longhorn. Click here to read more.

"We see this as the default platform on PCs in the next few years. Most of our applications are supported by 32-bit under 64-bit Windows. Some of our applications, like Office and others on the server, dont necessarily have to be 64-bit applications, as they can be run and supported in compatible mode," he said.

The naming of the product and its pricing are still being determined, Marr said, adding that theyd likely be close to the Windows 32-bit equivalent. While 64-bit would be a component of Longhorn, how it will be delivered has yet to be decided, he said.

Marr said the new security features of the upcoming Windows XP Service Pack 2 (SP2) will be included in the upcoming Windows 64-bit product. "Because we are shipping on the Server 2003 code base, we get all the reliability benefits of that for the client, and all the features and benefits of the XP SP2 will also all be incorporated into the next release," he said.

"Some of these are already in there, others are being moved across, and some will find their way in after XP SP2 has been released this summer," he said.

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