Need help with OBS performance issue

[Tahaan]

I don't record a lot, and usually it is just a short clip when I do.  Half the reason I don't record more is how terrible the performance is lately.

When I play the game with everything on LOW graphics settings I get 100 FPS or more.  

As soon as I start OBS the FPS still shows the same values, round-about the 90 to 110 mark... but the display stutters.  It is especially bad when you just turn from side to side.  Note that this is not recording - OBS is just running on another monitor.

I don't know what to call this display stutter.  It looks like low fps but the game still shows 100 fps (Using F8 to show the in-game fps counter)

Note that it used to be OK but then after installing updates I noticed that it is no longer any good.  Unfortunately since recording is something I often don't even think about for months between recordings I can't pin-point when it went bad exactly.

I last recorded in Alpha 18, but since then I've also had updates to OBS and to the operating system (Linux), and possibly significantly I'm on X now where I used to be on Wayland.  Perhaps I should try to get Wayland working.  I really noticed the issue after essentially everything updated in a short space of time - OS, OBS, and 7 days to Die all updated in a matter of a month so it is really hard to tell where the issue comes from.

For what it is worth: I am playing on an entry-level gaming laptop - MSI Leopard 8RE, i7 8750H, 24 GB ram, M2 and SSD drive, Nvidia 1060 mobile (6GB), running KDE neon 5.19, which is Ubuntu based with a current 5.4.0 kernel and Nvidia drivers 450.66.  OBS is version 25.0.8

 

[Liesel Weppen]

As soon as I start OBS the FPS still shows the same values, round-about the 90 to 110 mark... but the display stutters.  It is especially bad when you just turn from side to side.  Note that this is not recording - OBS is just running on another monitor.

I don't know what to call this display stutter. 

Tearing?

Du you usually use V-Sync, G-Sync or FreeSync? Maybe a running OBS breaks that.

 

[Tahaan]

My understanding of Tearing could be wrong but I think it is when you see half of one screen and half of another.

This is more like the game stutters.  Like very low FPS. 

About G-Sync / freesync.  I have an nVidia GPU so it would be G-Sync but I've never even heard of it and just googled it.  Seems it requires specific hardware support and my GPU - the 1060 - is not mentioned.  I assume my screen does not support it either.

I have V-sync turned off in the game.

So perhaps this is an issue related to Sync, so the next thing to try would be just to run with a single monitor and see if that is any better.  I should probably also try ask on the OBS forums.

I just did a quick test without the external monitor connected and still have issues though I think it is marginaly better.

Since Liesel mentioned it I checked for Tearing specifically.  I don't realy notice any in game while recording but the recording itself when I play it back has tearing.

 

[Liesel Weppen]

My understanding of Tearing could be wrong but I think it is when you see half of one screen and half of another.

Yep, and it especially occurs if you turn from side to side. If the tear off is small it is often confused with stuttering.

I have V-sync turned off in the game.

If V-Sync is off and no other sync is available, you'll get tearing anyway. (Or do you tripplebuffer?)

Turned of in the game doesn't necessarily mean it is not used, you can for example also force V-Sync in the Nvidia driver panel. You can also check that setting in your Nvidia control panel, and also try to change it and see if it helps (V-Sync on/off/fast).

So perhaps this is an issue related to Sync, so the next thing to try would be just to run with a single monitor and see if that is any better.  I should probably also try ask on the OBS forums.

Yep, if framerates are high, but it still looks like stuttering, it most times is a sync problem. That's why i asked if you are using any kind of sync. If you do not sync anyway, there shouldn't be a problem, but if you try to sync but it fails somehow, the outcome often is what you describe.

I don't know how OBS works in detail, but i can imagine, that especially a recording software may interfere at that point. Maybe it tries to sync to the framerate OBS is recording or similar?

 

[Tahaan]

Thank you, that is useful info.

I also googled it and finding more results and clues now that I know to look for tearing.

There are some suggestions for settings in the nVidia control panel that I am going to try.  

 

[Beelzybub]

@TahaanI had the same problem in Linux where running OBS would cause a stuttering, even though the frame rate

was still high. I fixed it by turning off desktop composition. Not sure what version you are running but on my machine

it is done by going to Settings/Desktop Settings, and then selecting the Window Manager.

It looks like this: