Question / Help [OBS STUDIO] Recording drops frames for only about 10 seconds, then goes back to normal

[danny03]

This issue has been boggling my mind for quite a bit of time, and it's gone on enough for me to finally post a thread to try to figure it out. When I hit F1 (my hotkey to start recording), OBS goes into a "Not Responding" state for a few moments, then starts recording. However, then, my recording freezes (experiences encoding lag) for about 10 seconds. After this, no other major lag issues occur.

Here is a log file:
https://pastebin.com/UvRDfC2g

 

[Harold]

output mode: simple
recording Quality: indistinguishable
recording format: FLV (don't save to mp4)
encoder: nvenc.

 

[danny03]

Unfortunately, this did not fix the issue. Even after resetting to factory default settings (using the settings you posted), the recording still freezes for about 7 to 10 seconds. Another thing to note: When recording starts, the recording is normal for about 1 second before it freezes for ~10 seconds. Also, if it's worth mentioning, while this is happening, it's taking less than 2% of CPU usage.

 

[Benman2785]

Output 'adv_file_output': Number of skipped frames due to encoding lag: 796 (40.5%) -> you drop a shitload of frames

u use NVenc -> try to set it to default and then use better settings (others have to provide them - im in the #redteam)
have in mind NVenc will need a lot of memory bandwidth -> be sure to run your GPU as PCIe 16x -> also make sure that if your GPU is under heavy load from game (due to max details) you should lower your graphics // NVenc may result in Input-lag // and with current Nvidia drivers the FrameReference is now done by CPU (so you will have higher CPU load then before - but better Quality)

 

[Benman2785]

wait - do u start the recording by clicking on the button while you are on the desktop and then switch back to the game? -> use a hotkey for recording

 

[Harold]

Show a new log with the settings I gave you.

 

[danny03]

Show a new log with the settings I gave you.

OK... Here's a new log with the new settings, also now at 30fps at 1280x720 resolution.
https://pastebin.com/BNxNanVd

 

[Benman2785]

Output 'simple_file_output': Total encoded frames: 1727
18:05:58.383: Output 'simple_file_output': Total drawn frames: 1728
18:05:58.386: Output 'simple_file_output': Number of skipped frames due to encoding lag: 164 (9.5%)
18:05:58.387: Output 'simple_file_output': Number of lagged frames due to rendering lag/stalls: 3 (0.2%)

better

 

[Benman2785]

cqp: 14 ??? there is no need for that -> try 18 or 22 or even 25 -> otherwise you have more load on gpu

but yet still i know more about AMF - but QP of 14 is pretty high

 

[Harold]

Changing the cqp value has no bearing on encoder load.

 

[Benman2785]

well it SHOULD have -> lower QP should be more load on Encoder

 

[Harold]

Except it doesn't.

 

[Benman2785]

mh, maybe NVenc handle it different then all other encoder i know :p