Tell one thing that you miss after switching from another OS to Linux.

For me, it's Shared GPU memory.

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Shared GPU memory (as described in that article) is just how Windows decided to solve the problem of oversubscription of VRAM. Linux solves it differently (looks like it just allocates what it needs in demand and uses GART to address it, but I would like to know more).
So I'm curious what you mean when you say you miss it. Are you having programs crash OOM when running on Linux? Because that shouldn't be happening.
It's not ideal to be relying on shared gpu mem anyway (at least in a dgpu scenario). Kinda like saying you have a preference on which crutches to use.
- There is one game called Cities: Skylines 2 that always fills up my VRAM, so yeah, I'm getting an OOM, but on the VRAM (I have GTX 1660super with 6 gigs of VRAM and I have 32 gigs of system RAM). I encourage you to try playing this game with a moderately sized city and with this GPU.
  
  Assuming C:S2 uses DX and you're running it through proton/dxvk, it's ultimately the Vulkan driver's job to page to system memory correctly. This honestly sounds like you're seeing a bug. In that circumstance, it shouldn't crash, it should just hurt performance from all the paging. I see a couple of older issues where people were seeing exactly this kind of issue with DXVK+Nvidia.
  This old Witcher 3 one where they blamed it on Nvidia's memory allocator not playing well with linux THP (transparent huge pages). Disabling THP was a workaround.
  This other issue for several titles that were hitting memory alloc failures despite having tons of system memory, just as you describe. They try several workarounds, but ultimately they believe it was fixed by a driver update.
  One other thing to try is, idk if you're running the game in dx11 or dx12 mode, but apparently both exist. If it's currently running in dx11 mode, try the launch flag -force-d3d12. If you're already using dx12, maybe try swapping back to dx11. Good luck!
  
  This honestly sounds like you're seeing a bug.
  Well, it probably is. I'll soon be getting a GPU with a bigger VRAM and putting that GPU into my home server for Jellyfin as a replacement for QuickSync (NVENC is better, imo).
  
  Did you try their fix? Often it really is as easy as adding a launch option
  
  I added game modern mangohud PROTON_ENABLE_NVAPI=1 %command% to the startup configuration and it still runs like shit. I'll try running it on a Windows VM (VMware as a hypervisor).
  
  I meant the:
  -force-d3d12
  one. Might need to put "%command%" after it, but I'm still not 100% sure what that even means and why its there so I dunno.
  Edit: I would also check out the entry for the game on ProtonDB if you haven't already (sorry if someone else has already told you all this elsewhere in the thread) to see if anyone else has had similar issues: https://www.protondb.com/app/949230
  I haven't played C:S2 yet, so I can't say personally, but it could just be a poorly optimized game.
  
  The -force-d3d12 option is a param to the actual game, so it would go after %command% (or by itself if no prefixes are being added).
  
  "Runs like shit" is expected when you're relying on paging to system memory every frame, step 1 is to avoid a crash from oom/failed alloc.
  The next step is to reduce paging if possible. I see C:S2 has a min spec of a 4GB GPU. Assuming they actually tuned their game for such a card on windows, the unfortunate reality of proton/DXVK is that there's a bit of a memory overhead and lack of knowledge about residency priority, especially when translating a dx11 game.
  DX12 maps to Vulkan more closely, so my hope is that the -force-d3d12 flag would give DXVK better info to work with (ex. hopefully the game makes use of dx12 heaps and placed resources, which are 1:1 with vulkan concepts, and dxvk can make use of that to better ensure the most important resources don't get paged out).
  
  C:S2 is a resource hog, even on Windows. The game still needs a lot of optimizations.

459 comments