Jim Allchin demonstrating preliminary WDDM in pre-release Windows Vista

[Ian W]

While searching through local files I discovered a video of former Windows chief Jim Allchin demonstrating a preliminary version of the Windows Display Driver Model (WDDM), then known as the "Longhorn" Display Driver Model (LDDM). Recall that WDDM was introduced in Windows Vista, and brought with it numerous benefits including display graphics fault-tolerance, the ability to update graphics drivers without restarting the system, and GPU virtualization and scheduling. Note that the latter two capabilities are required by the Desktop Windows Manager, and were so important during the development of Windows Vista that Microsoft's Greg Schechter stated that one "cannot overstate the importance of virtualization of the GPU in the same way the CPU has been virtualized."

Video link: http://1drv.ms/1WnaqHe

This video features Jim Allchin demonstrating XPDM on one machine and WDDM on another machine. Allchin opens several concurrent GPU-intensive applications on each machine, only for the XPDM machine to stutter and eventually run out of video memory. However, the WDDM machine has enough memory—in spite of eventually having additional applications open—and is also able to operate at better performance.


Image courtesy: Paul Thurrott

This video was originally uploaded by former Neowin writer Tom Warren, also known as "creamhackered."

[ViperAFK]

[PGHammer]

WDDM's flaws were on integrated GPU chipsets and extremely low-end chipsets (pretty much any non-ATI or non-nVidia graphics chipset); with Intel and S3 being the biggest offenders (both were also quite commonplace in low-end XP boxes in the consumer-stable and corporate-stable areas) .  nVidia discrete GPUs were fine; the same applied to ATI (AMD hadn't acquired them yet); the later forays into integrated graphics (by both companies) were also fine; however, it DID take Intel longer to fix those woes.  In short, the issues were with specific companies and chipsets - not integrated graphics as a whole.

[binaryzero]

S3... Geez, now we're turning on the flux capacitor. 

[Ian W]

It is 2015 and users are still able to successfully recover from faults and hangs—instead of witnessing a blue screen—because of Windows Vista and WDDM.

[Osiris]

Yep, despite the fact that Vista is considered a market failure, it was great they continued to build on it for Win7, rather than going back to base, nice little improvements like this lived on. 

Thanks for sharing the blast from the past

[Ian W]

For those interested, the earliest known references to the WDDM can be found here. This set of slides is from WinHEC 2002 and is so early that it does not even refer to the driver model as its preliminary name "LDDM," but instead refers to it as a set of significant improvements over XPDM.

Several features are listed in these slides, such as display dimming, driver upgrades without reboots, and timeout detection and recovery. While this list of features does not go into the level of detail that one would expect when compared with later documentation, it is nice to have insight into Microsoft's thought process during this time period. Note that WinHEC 2002 is also the source for the earliest known references to the Desktop Window Manager.

[binaryzero]

WHy bring this thread back from the dead?

Yep, old technology, cool, move on...

[tompkin]

WHy bring this thread back from the dead?

Yep, old technology, cool, move on...

Technology for it's own sake is a nice hobby but is not what most people care about (unless your in the tech industry).

Let's say you by a refrigerator. 4 years from now your refrigerator is still working fine. Is that refrigerator  "old technology" and you should go out and buy a new one? 

No. Why? Because the refrigerator you have is doing everything that you want it to. Probably will do virtually everything a new one will.

Most people don't upgrade because what they already have does everything they want it to. It's really not because their "stuck in their ways".

[Ian S.]

Talk about recording with a potato

[The_Decryptor Veteran]

WHy bring this thread back from the dead?

Yep, old technology, cool, move on...

I wouldn't call it old technology, it's still the current driver model in Windows 10 (Upgraded of course)

WDDM is the reason we can do crazy things like run a Direct3D app and a OpenGL app side by side, and gives us stuff like Direct2D (That can share surfaces with classic GDI rendering codepaths, etc.)