When recording with "Use GPU Recording" on, it is required to toggle "Threaded Video" to get smooth gameplay

I have this problem and found a workaround. But it is not a real solution and needs to be addressed in RetroArch itself. The problem happens regardless of the core. Below are files included, about my system information, RetroArch verbose output and nvenc configuration.

RetroArch: 1.10.3 (Git 9b282aa742) - Built: Apr 26 2022
OS: Manjaro Linux [x86_64]
Kernel: 5.17.9-1-MANJARO
[Vulkan]: Found GPU at index 0: "NVIDIA GeForce GTX 1070".
[Vulkan]: Found vulkan context: "vk_x".
[Vulkan]: Detecting screen resolution: 2560x1440.
[X/Vulkan]: Window manager is LG3D.
[Video]: Average monitor Hz: 143.760782 Hz. (4.017 % frame time deviation, based on 2048 last samples).

Description

Starting the video recording to file at full resolution (1440p) with a shader and setting "Use GPU Recording" enabled, makes the game very choppy to play the game from that point. As if my PC could not handle it, but it should and it can. The produced video file is still perfectly fine, it is only the gameplay session very slow and choppy to play.

Workaround: While recording to file, open RetroArch menu and toggle "Threaded Video" ON/OFF. This will fix the choppy and slow gameplay session and solves the above described problem. The previous state of the option does not matter, as long as it is toggled at least once.

Note: Having the option "Threaded Video" set to ON or OFF before starting the video recording has no effect in context to this problem.

Expected behavior

Start recording without the need to toggle option "Threaded Video" to get smooth gameplay while recording is happening.

Actual behavior

Stutter and choppy gameplay, unless I toggle "Threaded Video".

Steps to reproduce the bug

Option "Use GPU Recording" should be enabled in menu "Recording" prior the below steps.

1. Start any core.
2. Start recording video file.
3. Toggle option "Threaded Video" to get smooth gameplay while recording.

Bisect Results

It seems to be an old bug, but I only encountered it lately because I never tried to record with RetroArch prior to this. I became aware of the issue about 2 months ago here: https://github.com/libretro/RetroArch/issues/7841

Version/Commit

• RetroArch: 1.10.3/9b282aa742

Environment information

• OS: Manjaro
• Compiler: ---

mysyestem.txt
retroarch-output_recording.txt
nvidia-mysettings.cfg.txt

Reproduce the issue with RetroArch 1.10.3 on the reported Vulkan/NVIDIA setup, using the attached system information and verbose recording output as references. Start by tracing the recording path and the Threaded Video setting, then verify that GPU recording at full resolution remains smooth without toggling Threaded Video.