How much VRAM should I aim to fill before performance/stutters creep in?

Discussion in 'Videocards - NVIDIA GeForce Drivers Section' started by BlindBison, Jul 15, 2021.

  1. BlindBison

    BlindBison Master Guru

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    For example, I have a 2080 S and play at 1440p.

    Some games like Hunt Showdown let you choose a percentage of VRAM to target (70, 80, or 90%) and they list a note saying that it can improve performance to let the game use more VRAM but you need some VRAM overhead for the OS/background tasks and if the Driver tries to manage the VRAM allocation it can cause issues if the game's usage is too high they say on their in-game note.

    I noticed when I max the game out at 1440p and target 90% I get these occasional long hitches, but that seems to go away at 80% (which is the default value).

    I noticed a similar issue in Resident Evil Village which at Native 1440p max settings fully consumes all of the GPUs VRAM and led to extremely depressed performance.

    What I'm wondering then is, should I always aim for about 80% VRAM capacity usage for every game? Or, do you just want to make sure you never run out of VRAM so aim for more like 90%? I track the usage via HWiNFO64 in real time and typically make adjustments if I reach 8 gigs/full capacity, but I'm not sure how much overhead I need to leave on the table.

    Other games like Battlefield V have a built in setting which will guard against VRAM overfilling automatically which is neat, but anyhow thanks for your time.
     
  2. IceVip

    IceVip Master Guru

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    From my own experience, because I've screwed a lot with VRAM usage when making trailers, due to pushing past 6k res, it depends on the game. Every single engine reacts differently.
    There's no concrete answer except, if you don't fill it mor than 50%, you'll have no trouble. Some engines allow you to blow past all of your vram and act like nothing happened,
    especially if your page files are on an ssd/nvme. Because when you pass a specific threshold, it starts fetching from the page file, hence why in the task manager's performance tab
    in the gpu section, GPU Memory is always way bigger than the Dedicated GPU Memory, usually double its size or more. One thing i should mention is that when you close in
    on maxing out the vram, say its 7.2 out of 8, you've actually already crossed it and some of the required resources are inside the page file, open task manager and look at it for yourself,
    you'll see GPU memory is at 9.0 / 16.0 for example, whilst the Dedicated GPU Memory is at 7.2 / 8.0. That's would explain the hitches you get, because its trying to fetch stuff off of
    something that is around 150 times slower, even if the page file is located on an nvme.
     
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  3. dr_rus

    dr_rus Ancient Guru

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    Windows own DWM without any programs which use GPU rendering (browsers and such) tend to consume ~0.5GBs of VRAM.
    So if you have a 2080S with 8GBs of VRAM and you don't have anything VRAM consuming open in the background then you should use no more than 7.4GBs which means ~93%.
    Lower values may be used if you have higher base VRAM consumption depending on what is active alongside the game you're playing.

    But the answer above is also correct - what will happen once a game will get to a maximum amount of VRAM available is completely game dependent.
    Only thing to correct there is that the VRAM oversubscription go into page file - it's not, it goes into system memory and gets into page file only if the data isn't used for a very very very long time I believe. It is still an order of magnitude slower allocation than VRAM though and accessing it will result in either a hitch or a severe performance degradation.
     
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  4. IceVip

    IceVip Master Guru

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    Dammit I was wondering if it was the page file or the system memory. Thanks for the correction, OP replace page file with system memory in my post, and bring that 150 times slower down to 10. :D
     
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  5. BlindBison

    BlindBison Master Guru

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  6. Arinoki

    Arinoki Member

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    Who told u this? Btw, u can easily repeat this test - just close any software. (this is screenshot from GPU-Z, w/o telegram/chrome/etc opened)
    [​IMG]
     
    Last edited: Jul 16, 2021
  7. bluedevil

    bluedevil Master Guru

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    Hardware Unboxed has a 1060 3gb vs 6gb test video:
    More gddr capacity will help with future-proofing but by the time that more video memory is needed the gpu's processing power would become insufficient to maintain a good fps, say above 60.
    It also depends a lot on each game's memory management. As long as the GPU is continuously feed data and the video memory can catch from ram before it is needed then you won't get a performance penalty. A memory performance penalty might manifest itself with lower avg fps, lower 1% fps or even stuttering.
    I reckon that 6gb today is still ok for 1080p 8gb for 1440p and over 8gb for future-proofing.
    For individual games like Hunt Showdown you could use riva tunner to get a benchmark at different memory percentage targets but i would personally aim for the biggest gddr usage if there is no drop in performance.
     
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  8. BlindBison

    BlindBison Master Guru

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    Thanks!
     
  9. BlindBison

    BlindBison Master Guru

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    Just to clarify then, would aiming for maybe 7.5 GB usage out of 8 be the way to go do you think then? With HWiNFO64/RTSS I'm able to see the usage in real time so I figure that's a safe value to target then it can fluctuate somewhat without maxing out. Thanks,
     
  10. BlindBison

    BlindBison Master Guru

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    Unrelated, but your profile pic brings me back lol -- Bleach Seasons 1-3 were fire. First two arcs were great, then it kinda tanked imo. It's weird, even the art style is different/much more detailed in the early manga/seasons -- there are some interesting YouTube videos i've seen comparing the art panels from the early chapters VS hundreds of episodes later for example.
     
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  11. dr_rus

    dr_rus Ancient Guru

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    Sure but this is game dependent. Some games may hitch at this consumption, some can be fine.
     
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