WINDOWS SCHEDULER DRIVER
WINDOWS SCHEDULER FULL
WINDOWS SCHEDULER WINDOWS

WINDOWS SCHEDULER WINDOWS

With the right hardware and drivers, Windows can now offload most of GPU scheduling to a dedicated GPU-based scheduling processor. With Windows update, we are introducing a new GPU scheduler as a user opt-in, but off by default option. Applications may submit more frequently, in smaller batches to reduce latency or they may submit larger batches of work to reduce submission and scheduling overhead. There is a fundamental tension between latency reduction and submission/scheduling overhead. User input is picked up by the CPU during “frame N+1” but is not rendered by the GPU until the following frame. This buffering of GPU commands into batches allows an application to submit just a few times per frame, minimizing the cost of scheduling and ensuring good CPU-GPU execution parallelism.Īn inherent side effect of buffering between CPU and GPU is that the user experiences increased latency. For example, an application would typically do GPU work on frame N, and have the CPU run ahead and work on preparing GPU commands for frame N+1.

These overheads have been mostly masked by the way applications have traditionally been written. This approach to scheduling the GPU has some fundamental limitations in terms of submission overhead, as well as latency for the work to reach the GPU. We have always had a high-priority thread running on the CPU that coordinates, prioritizes, and schedules the work submitted by various applications. However, throughout its evolution, one aspect of the scheduler was unchanged. Over time we have significantly enhanced the GPU scheduler at the heart of WDDM, supporting additional features and scenarios with each new WDDM version. With the transition to a broad set of applications using the GPU for richer graphics and animations, the platform needed to better prioritize GPU work to ensure a responsive user experience.

WINDOWS SCHEDULER FULL

These very rudimentary scheduling schemes were workable, at a time where most GPU applications were full screen games, being run one at a time. They submitted to a global queue where it was executed in a strict “first to submit, first to execute” fashion. Few likely remember the pre-WDDM days where applications could simply submit work to the GPU as much as they wanted.

WINDOWS SCHEDULER DRIVER

It has been almost 14 years since the introduction of the Windows Display Driver Model 1.0 (WDDM) and with it the introduction of GPU scheduling in Windows. As the graphics platform continues to evolve, this modernization will enable new scenarios in the future.

It is one of those things that if we do our job right, you will never know the transition happened. For most users, this transition will be transparent. Hardware Accelerated GPU Scheduling enables more efficient GPU scheduling between applications. Remaining on the cutting edge of hardware innovation has always been a critical aspect of our graphics platform. It is intended for folks curious about Windows internals. The purpose of this blog is to give some background on this new feature and how we are introducing it. You may have noticed a mysterious new optional feature called Hardware Accelerated GPU Scheduling appear in the advanced graphics settings page with the Windows update.

Windows scheduler