Windows Display Driver Model - Wikipedia, the free encyclopedia. Windows Display Driver Model (WDDM)[1] is the graphic driver architecture for video carddrivers running Microsoft Windows versions beginning with Windows Vista.[2]It is a replacement for the previous Windows 2. Windows XP display driver model XDDM/XPDM[3] and is aimed at enabling better performance graphics and new graphics functionality and stability.[2] Display drivers in Windows Vista and Windows 7 can choose to either adhere to WDDM or to XDDM.[4] With the removal of XDDM from Windows 8, however, WDDM became the only option.[5]WDDM provides the functionality required to render the desktop and applications using Desktop Window Manager, a compositingwindow manager running on top of Direct. D. It also supports new DXGI interfaces required for basic device management and creation. The WDDM specification requires at least Direct. D 9- capable video card and the display driver must implement the device driver interfaces for the Direct. D 9. Ex runtime in order to run legacy Direct.
View a list of keyboard shortcuts (also called access keys, shortcut keys, and key combinations) for using Windows features. Windows Display Driver Model (WDDM) is the graphic driver architecture for video card drivers running Microsoft Windows versions beginning with Windows Vista. Introductory Vista Tutorials. Some of the free Windows Vista tutorials already available include customizing your desktop in Vista, and our tutorials on Windows Vista.
Troubleshooting steps to resolve the error message: Display driver stopped responding and has recovered. One of the biggest annoyances for me in Windows 7 or Vista is that you can’t immediately open the Network Connections list to see the list of adapters like you.
D applications; it may optionally implement runtime interfaces for Direct. D 1. 0/1. 0. 1 and higher. Features enabled by the WDDM[edit]WDDM drivers enable new areas of functionality which were not uniformly provided by earlier display driver models. These include: Virtualized video memory[edit]In the context of graphics, virtualization means that individual processes (in user mode) cannot see the memory of adjacent processes even by means of insertion of forged commands in the command stream. WDDM drivers allow video memory to be virtualized,[6] and video data to be paged out of video memory into system RAM. In case the video memory available turns out to be insufficient to store all the video data and textures, currently unused data is moved out to system RAM or to the disk. When the swapped out data is needed, it is fetched back.
Virtualization could be supported on previous driver models (such as the XP Driver Model) to some extent, but was the responsibility of the driver, instead of being handled at the runtime level. Scheduling[edit]The runtime handles scheduling of concurrent graphics contexts.[7] Each list of commands is put in a queue for execution by the GPU, and it can be preempted by the runtime if a more critical task arrives and if it has not begun execution. This differs from native threads on the CPU where one task cannot be interrupted and therefore can take longer than necessary and make the computer appear less responsive. A hybrid scheduling algorithm between native and light threads with cooperation between the threads would achieve seamless parallelism. It is important to note that scheduling is not a new concept but it was previously the responsibility of individual driver developers. WDDM attempts to unify the experience across different vendors by controlling the execution of GPU tasks.
Cross- process sharing of Direct. D surfaces[edit]A Direct. D graphics surface is the memory area that contains information about the texturedmeshes used for rendering a 2. D or 3. D scene. WDDM allows Direct. D surfaces to be shared across processes.[8] Thus, an application can incorporate a mesh created by another application into the scene it is rendering. Sharing textures between processes before WDDM was difficult, as it would have required copying the data from video memory to system memory and then back to video memory for the new device. Enhanced fault- tolerance[edit].
Windows Vista alerting the user of a successful WDDM recovery. If a WDDM driver hangs or encounters a fault, the graphics stack will restart the driver.[2][9] A graphics hardware fault will be intercepted and if necessary the driver will be reset. Drivers under Windows XP were free to deal with hardware faults as they saw fit either by reporting it to the user or by attempting to recover silently.
With a WDDM driver, all hardware faults cause the driver to be reset and the user will be notified by a popup; this unifies the behavior across vendors. Previous drivers were fully implemented in kernel mode, whereas WDDM is implemented partly in user mode. If the user mode area fails with an unrecoverable error, it will, at the most, cause the application to quit unexpectedly instead of producing a blue screen error as it would in previous driver models. WDDM also allows the graphics hardware to be reset and users to update drivers without requiring a reboot.[2]Limitations[edit]The new driver model requires the graphics hardware to have Shader Model 2.
However, according to Microsoft as of 2. Windows Vista used the XDDM,[1. WDDM capable. It also requires some other hardware features; consequently some SM 2. Intel GMA 9. 00 fails the WDDM certification.[1. One of the limitations of WDDM driver model version 1. If a multi- monitor system has more than one graphics adapter powering the monitors, both the adaptors must use the same WDDM driver.
If more than one driver is used, Windows will disable one of them.[1. WDDM 1. 1 does not have this limitation.[1. WDDM 1. 0/1. 1 does not allow some modes that were previously handled by the driver such as spanning mode (stretching the desktop across two monitors)[1.
Dual View is still available.[1. Need for a new display driver model[edit]One of the chief scenarios the Windows Display Driver Model enables is the Desktop Window Manager. Since the desktop and application windows managed by DWM are Direct. D applications, the number of open windows directly affects the amount of video memory required. Because there is no limit on the number of open windows, the video memory available may prove insufficient, necessitating virtualization. As the window contents that DWM composes into the final desktop are generated by different processes, cross- process surface sharing is necessary.
Also, because there can be other Direct. X applications running alongside DWM on the DWM- managed desktop, they must be able to access the GPU in a shared manner, necessitating scheduling. Though this is true for Microsoft's implementation of a composited desktop under Windows Vista, on the other hand, a composited desktop need not theoretically require a new display driver model to work as expected.
Successful implementations of composited desktops were done before Windows Vista on other platforms such as Quartz, Compiz, Window. FX. The approach Microsoft attempted was to try to make sure WDDM was a unified experience across different GPUs from multiple vendors by standardizing their features and performance. The software features missing from other driver models could be made immaterial by extensions or if a less restrictive or simply different driver model was in place. History[edit]WDDM 1.
Windows Vista introduced WDDM 1. HDCP.[1. 7]WDDM 1. Windows 7 supports major additions to WDDM known as WDDM 1. Win. HEC 2. 00. 8. New features include: [1. Hardware acceleration of GDI and Direct. D/Direct. Write operations helps reduce memory footprint in Windows 7, because DWM compositing engine no longer needs to keep a system memory copy of all surfaces used by GDI/GDI+, as in Windows Vista.[2.
DXGI 1. 1, Direct. D 1. 1, Direct. 2D, and Direct. Write were made available with Windows Vista Platform Update; however GDI/GDI+ in Vista continues to rely on software rendering[2. Desktop Window Manager continues to use Direct. D 9. Ex.[2. 6]WDDM 1. WDDM 1. 0 specification; both 1. Windows Vista with or without the Platform Update.[1.
WDDM 1. 2[edit]Windows 8 includes WDDM 1. DXGI 1. 2.[2. 8][2. New features were first previewed at the Windows BUILD 2. D rendering and video playback. Other major features include preemptive multitasking of the GPU with finer granularity (DMA buffer, primitive, triangle, pixel, or instruction- level),[3. Windows 8, and Direct. D 1. 1 Video supports YUV 4: 4: 4/4: 2: 2/4: 2: 0/4: 1: 1 video formats with 8, 1.
WDDM 1. 0/1. 1 only allows rudimentary task scheduling using "batch queue" granularity; improvements to multitasking, as well as fast context switching and support for virtual memory, were initially expected in versions tentatively named WDDM 2. WDDM 2. 1, which were announced at Win. HEC 2. 00. 6.[3. 2][3. WDDM 1. 3[edit]Windows 8.
WDDM 1. 3[3. 5] and DXGI 1. New additions include the ability to trim DXGI adapter memory usage, multi- plane overlays, overlapping swap chains and swap chain scaling, select backbuffer subregion for swap chain and lower- latency swap chain presentation. Driver feature additions include wireless displays (Miracast), YUV format ranges, cross- adapter resources and GPU engine enumeration capabilities. WDDM 2. 0[edit]Windows 1. WDDM 2. 0, which is designed to dramatically reduce workload on the kernel- mode driver for GPUs that support virtual memory addressing,[3. CPU utilization.[3. Direct. 3D 1. 2 API, announced at Build 2.
WDDM 2. 0. The new API will do away with automatic resource- management and pipeline- management tasks and allow developers to take full low- level control of adapter memory and rendering states. References[edit]^"Windows Display Driver Model (WDDM) Design Guide". MSDN. Microsoft. Retrieved 1. February 2. 01. 5. ^ abcd"Windows Vista Display Driver Model".
MSDN. Microsoft. July 2. Retrieved 9 December 2. XPDM vs. WDDM". MSDN.
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Windows 2. 00. 0 Display Driver Model (XDDM) Design Guide". Windows Dev Center - Hardware. Microsoft. 1. 6 November 2. Retrieved 9 December 2. Roadmap for Developing Drivers for the Windows 2. Display Driver Model (XDDM)". Windows Dev Center - Hardware.
XDDM and VGA drivers will not compile on Windows 8 and later versions ^"Graphics Memory Reporting through WDDM". MSDN. Microsoft. 9 January 2. Retrieved 9 December 2. Schechter, Greg (2 April 2.
The role of the Windows Display Driver Model in the DWM". Greg Schechter's Blog. Microsoft. Retrieved 9 December 2.
Cross Process Resource Sharing". MSDN. Microsoft. 1. December 2. 00. 9.
Retrieved 9 December 2.