CPU GPU utilization in VR

Discussion in 'Technical & Support' started by Jego, Nov 5, 2018.

  1. Jego

    Jego Registered

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    I know, this has been discussed a few times already, however I still can't really get the max out of my system.
    I recently got a Ryzen 2700x (No OC, great CPU cooler) 16GB 3200Mhz Ram and a RTX 2080 (No OC)
    (I know, AMD has a low Single Core Performance)

    When I am in VR with a big grid, my frames drop significantly, even when I have all settings on low and supersampling off.

    Here are too example videos of the load on my system.
    40 AI run at Silverstone short one lap.(I was not wearing headphones and sitting next to my wheel so ignore the sounds of my driving. :rolleyes:)


    Run 1:

    Supersampling: 0

    [​IMG]
    [​IMG]

    Video: https://streamable.com/h0drt

    With those settings it ran at 90FPS and had a headroom of 20-30%. As you can see the system is never fully loaded. Alright, why would it, here is enough headroom.


    Run 2:

    Supersampling: 1.4

    [​IMG]
    [​IMG]

    Video: https://streamable.com/q3bwv

    Here it still ran with 90FPS, however the headroom was between -10% and 5%. So the FPS dropped below 90 several times when something in front of me happened.

    As you can see from the video, the CPU usage of any of the cores was never really above 85%.

    What can I do to get the extra 15% of my CPU to be used.

    I just tried the same settings as in the last run with "Use thread":False and it appears that rfactor uses 5% more of the core then.
    However, it's still only 90%.
     
    Last edited: Nov 5, 2018
  2. patchedupdemon

    patchedupdemon Registered

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    Why do you want to use 100% of cpu, you should always look to have some headroom left.
     
  3. Jego

    Jego Registered

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    Well, it is not using so much most of the time anyways, when you look at the 2nd video the core load is mostly at 80%, sometimes 90 sometimes 70. However as I said, my FPS were dropping below 90FPS and my Headroom was below -5% most of the time. So I would it expect to work harder to at least gain some Headroom to maintain the 90FPS.
     
    Last edited: Nov 5, 2018
  4. Lazza

    Lazza Registered

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    I think any time there is actual live output involved you shouldn't be expecting full 100% occupancy. You'd get that if you had the game code sitting there nicely with all your inputs queued up and ready to write, say, a video of the resulting session, which your PC could write as fast as possible to disk (or memory, for speed). But as soon as you actually need to output and adjust in real time you will tend to fall back from that 100%.

    I don't have technical knowledge of how CPU/thread occupancy is measured over each time slice, so whether that's an additional factor, but from a live process point of view I think you immediately start to limit how much of that CPU resource you're able to use.
     
  5. CoNa

    CoNa Registered

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    Have you tested to set HMD only and lower you resolution a bit, as it should give you some more frames and lower the load. That way you can increase the eyecandy instead.
    No need to have hmd+mirror unless someone else is watching you race on the main monitor.
     
  6. sherpa25

    sherpa25 Registered

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    Haven't tested the difference, but I've read some say it makes no significant difference.
     

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