Temporarily Disabling DWM to reduce VRAM usage in Windows 10?

[g67575]

I noticed that DWM can consume 200-400MB of VRAM in Windows 10.

There are some games that would probably benefit from a few hundred MB of extra VRAM (to avoid stuttering or freezing problems). So, is it possible to temporarily disable the DWM process in Windows 10, to leave this VRAM clear for use in games?

 

[g67575]

It's too bad that any attempt to completely disable DWM.exe will make Windows 10 unbootable (I had to use a system restore point to boot Windows 10 again). It's no longer an optional part of Windows, like with Windows 7 and Vista. There used to be an option to disable it while running games in Windows 7.

I noticed when running Watch Dogs: Legions that DWM.exe can use upto 500-600 MB of VRAM.

DWM is apparently also responsible for enforcing Vsync in windowed / borderless windowed games...

 

[g67575]

Hi, I found out that you can suspend 'winlogin' from the resource manager, then close dwm completely, but it didn't solve my vram issue with the rtx 3070 in WD: Legion.

 

[g67575]

Success in Watch Dogs : Legion I think!

I completely disabled DWM.exe after starting the game, with 'texture resolution' set to 'High'. In game, I saw VRAM usage rise to 7900-8000 MB of VRAM. I ran the game in windowed mode (I think fullscreen caused problems with DWM not running).

More interestingly, the 'Shared GPU Memory' rose to ~600MB, this basically means the game exe was using 600MB of RAM as a substitute for VRAM, with no freezing in game

I then set texture resolution to 'Ultra', and again there was no freezing in game (tested for 40 minutes in total, driving around on a fast bike).. I couldn't monitor VRAM / shared GPU usage because task manager bugged out at this point.

I need to do some more testing to see if it's another setting in game causing these VRAM issues. But, it looks like the game using 'shared GPU memory' (or not) could be the problem.

 

[g67575]

To turn off DWM.exe while playing, I did this:
1. Ran the game, set it to run in 'Windowed mode'
2. Suspended Winlogin.exe in Resource monitor (so that DWM.exe doesn't restart itself)
3. Ran a bat file with these commands:
taskkill /im explorer.exe /f
taskkill /im ApplicationFrameHost.exe /f
taskkill /im ShellExperienceHost.exe /f
taskkill /im TextInputHost.exe /f
taskkill /im SearchApp.exe /f
taskkill /im dwm.exe /f
Taskmgr.exe

I monitored dedicated and shared GPU memory in task manager during gameplay.

I suspect that the problem is that WD: Legions is not using enough 'Shared GPU Memory', once the VRAM is at capacity / near to the limit, leading the game to freeze (for 30 seconds or more) while the VRAM amount is adjusted.

I will test this on 'Ultra Texture Resolution' at 4K now, with DWP.exe + everything running as normal.

 

[g67575]

I just got a freeze followed by a game crash with DWM.EXE enabled + ultra texture resolution on. VRAM usage was 7.5GB, with 600-700MB of 'shared GPU memory'.

 

[g67575]

Unfortunately, I've been getting freezes in gameplay on High settings too, which seems to be common with graphics cards with 8GB VRAM for this game.

Maybe I'll just leave it on high (and see if it keeps freezing repeatedly in one session), as I keep getting game crashes when it's set to Ultra texture resolution.

 

[g67575]

I'm pretty sure the problems I've been having are related to the page file. Watch Dogs Legion seems to use it a massive amount, particularly after the game freezes. I noticed that the freezing intervals were shorter after I moved the page file to the same drive where the game is installed.

These problems only seem to occur when lots of VRAM is being utilized (on High / Ultra textures).

There were similar problems with Watch Dogs 2 apparently, according to this:
https://forums.ubisoft.com/showthread.php/882136-Freezes-for-seconds-at-a-time-Forums

I think as the game assets load during gameplay, if VRAM is at capacity, it loads graphics data into the pagefile, and then to 'Shared GPU Memory' (in other words RAM). While the data is transferred from the slow page file (on your disk), to the much faster RAM, the game freezes.