HAGS - Hardware Accelerated Graphics Scheduling As the name implies, this feature is regarding GPU tasks that are queued to be performed on hardware as opposed to software. So what software performs these tasks? My limited understanding is that it can be from API level (so features of DirectX/OpenGL/Vulkan etc) driver level, OS or other methods. What I wonder though, is this feature (that is very difficult to enable in the first place) worth activating? The reason I created this thread is that there's ongoing discussion in several of the driver threads about this feature that people seem to have little understanding about, many conflicting arguments and statements about the feature so figure if people can pool their knowledge and collate it here, maybe we can come to a definitive conclusion. Now as far as I understand (and no doubt my understanding is very limited so I've probably got something wrong somewhere) AMD and Nvidia GPUs approach scheduling differently. In AMDs cards, the GPU itself is responsible for managing its resources and handles calls and dispatches etc (from my memory this caused AMD difficulty in optimising drivers for games in the past and probably still does), they already make use of hardware schedulers whereas Nvidia dropped the use of a hardware scheduler with the launch of the Kepler, or rather had a fixed width scheduler which they used software to optimise scheduling tasks (why the hardware requires game ready drivers and also why ever more powerful Nvidia GPUs require much more powerful CPUs to support the drivers). So I wonder, what makes HAGS on AMD different? To me, if AMD GPUs already use hardware scheduling, isn't this just a redundant feature and perhaps why it's not being enabled or actively implemented etc? I think being able to discuss this would give greater understanding for us all, I certainly have no idea about the topic and can't seem to find any clarification myself and it doesn't help that the fragmented discussions in the various driver threads add to this confusion.
is black magic, nah just kidding, wait for somebody who really knows about this, something better is coming i believe
I was getting some performance benefit from it on my 6800XT, one specific example is Horizon: ZD. But it mostly didn't change much. Some people were reporting better 1% lows, but I didn't see that.
from all the info it seems to be some more direct way (shortcut) for Windows to use your GPU more efficiently it messes up the performance if it takes away resources from the game, but seems to help if the game is made with newer Windows versions in mind(since HAGS was introduced) wierdness around when it accidently helps if game uses the same things that GPU stuff is scheduled with?? with AMD gpus it seems to create mess around this, help with some stuff and not so helpful with other stuff, so overall its not beneficial?
The most impressive gap I know of is with capture and streaming software. There is some overhead associated with desktop capture itself which is reducing GPU utilization slightly due to context switching between the game, capture app (OBS, Sunshine, etc), and DWM (the Windows desktop compositor) where the frames are captured by the OS. While they are performing capture and encoding, the game is not issuing more 3D work, so you see slight drops in 3D usage. The higher the stream FPS, the more often they are interrupting the game to capture and encode the latest frame. There's some fixed context switching overhead each time this happens, so higher capture rate means higher performance overhead. Enabling Hardware-Accelerated GPU Scheduling significantly reduces the performance reduction due to desktop capture by improving context switching performance.
But on my 7900XT OBS works fine with HAGS. I still wonder if it really works because I don't see any difference with HAGS on and off. No change in the performance and stability. I have tested it with the proper UWP 39003 driver (with official HAGS support) - not with suspicious registry hacks and emulations.
Well, my experience was with 4070. Edit: Might have been the same with the 6700 XT & the UWP drivers, can't recall.
I remember that many owners of AMD cards had problems with this combination - HAGS + OBS. We have discussed that in the UWP drivers thread. P.S. Actually, we had HAGS support with an older driver as well - UWP 31.0.22000.11008.
