Missing frames and rendering lag with barely used GPU/CPU

[NioZero]

Hi OBS team.

I hope you can help me, because I tried a lot of things but I keep having issues. I have a dedicated capture/streaming desktop and for some reason is missing a lot frames and have rendering lag. If I reduce the resolution, the framerate or the bitrate, the results doesn't change. I am using NVENC encoding but I have also tried the x264 encoding with the same results. I have upload the log to the analyzer but the suggestions doesn't work for me because this is a dedicated PC and it seems like the suggestion are from a traditional setup. My PC has plenty of resources to render a more complex scene and it's rarely used for other purpose. The framerate is always in the range of 55~56fps, but when I reduce the framerate, like for example 30, is now at 27~28 fps.

Things I tried
- reducing resolution
- reducing framerate
- reduced bitrate or recording local only
- changed from NVENC to x264 with different profiles
- created a more simple scene with fewer elements

The hardware is the following
CPU: AMD Ryzen 7 3700X
GPU NVIDIA GTX 1660 super
RAM: 16 GB
Capture Card: elgato 4K60 Pro MK.2

This is some screenshot with my latest stream (here's the VOD with the notorious lag)
I

The GPU is always lower thant 50% and the CPU is barely in the 10%...

I don't know what is causing the issue, maybe some specific element or something else. Is there a way to know what is causing the lag? I have uploaded the log and here is the analyzer results

Analyzer | OBS

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[qhobbes]

AFAIK the replay buffer uses the recording settings. Change preset to quality and uncheck lookahead and psycho.

21:04:41.460: [jim-nvenc: 'recording_h264'] settings:
21:04:41.460: rate_control: CQP
21:04:41.460: bitrate: 0
21:04:41.460: cqp: 18
21:04:41.460: keyint: 120
21:04:41.460: preset: mq
21:04:41.460: profile: high
21:04:41.460: width: 1920
21:04:41.460: height: 1080
21:04:41.460: 2-pass: true
21:04:41.460: b-frames: 2
21:04:41.460: lookahead: true
21:04:41.460: psycho_aq: true

 

[koala]

Is this a custom built PC? The Graphics card might not be operating in full x16 pci-express speed. Use GPU-Z and verify that in the "Bus Interface" field the x16 is displayed on both sides of the @, i. e. something like "PCIe x16 3.0 @ x16 3.0".
If it is lower, verify the seating of the card. It must be in a x16 capable slot. If there are multiple wide slots, it's usually the slot nearest to the CPU that has to be used.

 

[NioZero]

AFAIK the replay buffer uses the recording settings. Change preset to quality and uncheck lookahead and psycho.

21:04:41.460: [jim-nvenc: 'recording_h264'] settings:
21:04:41.460: rate_control: CQP
21:04:41.460: bitrate: 0
21:04:41.460: cqp: 18
21:04:41.460: keyint: 120
21:04:41.460: preset: mq
21:04:41.460: profile: high
21:04:41.460: width: 1920
21:04:41.460: height: 1080
21:04:41.460: 2-pass: true
21:04:41.460: b-frames: 2
21:04:41.460: lookahead: true
21:04:41.460: psycho_aq: true

This makes a lot of sense. I will try lowering the quality of the recording and/or disabling replay buffer just in case is that. I have a question about that option though.

"Maximum Memory" is related to GPU VRAM? RAM? or hard disk space?

Is this a custom built PC? The Graphics card might not be operating in full x16 pci-express speed. Use GPU-Z and verify that in the "Bus Interface" field the x16 is displayed on both sides of the @, i. e. something like "PCIe x16 3.0 @ x16 3.0".
If it is lower, verify the seating of the card. It must be in a x16 capable slot. If there are multiple wide slots, it's usually the slot nearest to the CPU that has to be used.

I checked GPU-Z and is fine. The GPU is in the main PCIe Slot and I always keep the drivers up-to-date.

This is the GPU-Z info if you're interested..

The current video drivers installed...

 

[NioZero]

So...

I did the following
- Reduced resolution to 720p
- Disabled Replay Buffer
- Change Recording to (use stream settings)

The results were practically the same. The GPU usage was obviously a little lower (30% at most) and the lag was the same.

I really don't know why is happening this. I hope you can help me.



Log Analyzer: https://obsproject.com/tools/analyzer?log_url=https://obsproject.com/logs/MYYdd4DMcOuvYnXZ

I have attached also de log

 

[FerretBomb]

Most commonly (as you are not using any CUDA-enabled encoding options) this is caused by either a capture conflict (but you aren't using any Monitor Captures), or a slow browser source which is unable to update in a timely fashion for each frame. Especially-so in cases where there are bandwidth stability issues (as appears to be the case from your logfile, during the streaming session).

If you run a test-stream with a fresh Scene Collection, does the frame delay issue still occur?

If you create a test log (as you did above) then exit out of OBS, restart OBS, go to Help->Log Files-> Upload Last Logfile, it will include a timing tree which is generated on exit which we can look over for more detailed analysis and hints on what's gumming up the works.