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Nvidia's Performance Under Vulkan API Explored

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]-[itman

Member
Joined
Sep 24, 2001
Location
Arizona
Just sharing what I found in benching with presentmon on Vulkan. First video is about Doom but will have a follow-up video shortly. Also doing more investigating into whether some of what I'm seeing is due to the tool or not. I'm not a video editor or a youtube personality by any means, this is just something I wanted to try so be nice :)

https://www.youtube.com/watch?v=23ldjYybTGI&feature=youtu.be

Results start at 2:30

jp09esb.png


*UPDATE*

Second video with Dota 2.

https://youtu.be/fAyG0AoWMZE
 
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Kenrou

Member
Joined
Aug 14, 2014
Have no idea what he meant, but from 361.91 OpenGL to 368.69 Vulkan it raised my fps in Doom from ~120 to ~190, so I'm happy with it I suppose ?
 
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OP
]-[itman

]-[itman

Member
Joined
Sep 24, 2001
Location
Arizona
Basically that even though your card is rendering the game at 190 fps, there seems to be a bug in Nvidia's Vulkan driver where it is forcing your frame rate to the refresh rate of your monitor (60 fps for a 60 hz monitor) but is dropping frames from not synching correctly. In other words, even though the game is rendered at 190 fps, you're probably averaging closer to ~50 fps from swinging between 60 fps to 0 fps over and over again. For Vulkan games right now, it's better to stick to OpenGL on Nvidia cards.
 

Kenrou

Member
Joined
Aug 14, 2014
Roughly the same fps on my screen with every counter i checked, Vulkan slightly in the lead.
 
OP
]-[itman

]-[itman

Member
Joined
Sep 24, 2001
Location
Arizona
Most counters don't work under Vulkan. Also, the other counters will only tell you how many fps are being rendered by your card, not how many are actually being sent to your monitor. You need to use presentmon to see the difference under Vulkan.
 

EarthDog

Gulper Nozzle Co-Owner
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Location
Buckeyes!
Interesting testing... cant say I experienced the suttuering though when using the Vulkan API...

I wonder if it has to do with the last gen card versus a 1080 like i have?
 
OP
]-[itman

]-[itman

Member
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Sep 24, 2001
Location
Arizona
It effects Pascal as well. It may be dependent on driver version, I'm looking into it more.
 

EarthDog

Gulper Nozzle Co-Owner
Joined
Dec 15, 2008
Location
Buckeyes!
I am running 368.81. Don't see it (the stuttering). Also running 4K with Low FXAA. SHows around 60-75 FPS (did not capture perfmon).

Be careful when requesting a fix that (may have) already been fixed! :)
 

Kenrou

Member
Joined
Aug 14, 2014
Don't see any stuttering as well at high/low fps @1080p ? maybe fixed ?
 
OP
]-[itman

]-[itman

Member
Joined
Sep 24, 2001
Location
Arizona
368.81 was driver used for testing, the issue is definitely present with this driver. A German website has tested this and found the same issue.

https://youtu.be/GFAqBkOo6z4

They go into even more detail but it's in German.
 

EarthDog

Gulper Nozzle Co-Owner
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Location
Buckeyes!
I don't 'see' it (stuttering)... sorry. I also don't do German so no clue what he is saying either. :(

Are the frame times still under that magic value where one sees/doesn't see stuttering? I don't know, perhaps I am not 'looking' hard enough, but, seems fine to me... :chair:
 
OP
]-[itman

]-[itman

Member
Joined
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Location
Arizona
It's more of a "microstutter" as it has become known as over the years. Basically, even though the fps is telling you it's higher in Vulkan, it's actually higher fps under OpenGL and is a smoother experience as there aren't any dropped frames. I definitely felt the difference when switching but some are more sensitive to it than others.
 

EarthDog

Gulper Nozzle Co-Owner
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Location
Buckeyes!
My FPS aren't really higher with Vulkan last I checked in another thread anyway... LOL

Thanks for the info.. I will keep an eye out on the testing. :)
 
OP
]-[itman

]-[itman

Member
Joined
Sep 24, 2001
Location
Arizona
Yes, it can't match the pid to a game executable. Can you double check the pid after you have doom loaded? If you restart the game the pid will change.
 

Kenrou

Member
Joined
Aug 14, 2014
redoing it now, as admin, in a admin command prompt, right PID but still giving off some kind of error ? sent to your email.


Edit: Online guide says i have to download "Visual express Studio" ?

Edit 2: doesn't the image in post #17 work ? "199.5 fps - 60.3 displayed fps" ? i can tell you there's a definitive bump in smoothness from 60fps vSync to off, doesn't feel/look placebo, its the same as going from 30fps to 60fps.
 
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OP
]-[itman

]-[itman

Member
Joined
Sep 24, 2001
Location
Arizona
Sorry, got busy this weekend. Your results show the same under win 8.1. You're rendering in the hundreds of fps but your card is only sending 60 fps to your monitor with lots of dropped frames. Vsync under Vulkan is broken AFAIK and causes even worse performance so that's probably why it feels smoother with it off. For Nvidia cards the best thing is still to run OpenGL instead of Vulkan.