Slowdown on Linux anyone else or just me?

[_c0rr0si0n_]

Hi all,

Running Dolphin 5 on my Ubuntu 16.04 box (i3-3225, 660ti, 8GB RAM) and trying to play Metroid Prime on the Gamecube. As soon as the intro video starts running I get a big frame hit down to 30fps. I've got the latest Nvidia drivers (Binary blob from nvidia.com) and tried the Vulkan and OpenGL renderers. I've also tried tweaking just about every setting to do with graphics I could find but it seems to make zero impact.

Has anyone else seen this on Linux? Maybe have some suggestions of things I can look for. I can see my CPU is pegging 100% utilization in top on a single core it looks like so maybe it's not utilizing all cores but I guess this could be design? Any tips on where I can start looking for the bottle neck? Is anyone else seeing anything comparable on Windows? I.e. is this just the speed it runs at?

[leolam]

Is it a very stable 30fps? If so, have you made sure v-sync is disabled?

Since you have a 660 Ti and use the proprietary driver, it should handle full speed just fine.

[_c0rr0si0n_]

It's 30fps lowest and varies a little up to say 40. I've struggled through the first "intro/training" level to the Chozo Ruins the frame rate seems to jump around a lot (never below 30 and can be as high as 60 in small rooms with no actors) so this is looking like it's something to do more with the intro video that plays in the background of the opening of the game? I might surrender and install Windows to see if that makes any odds when I get a chance.

[_c0rr0si0n_]

A bit more testing has come up with the following:

Testing my Laptop (Lenovo Z370, i5-2410M, Geforce 410M, 8GB RAM) Also on Ubuntu 16.04 with stock distro graphics drivers I see similar performance (30-40fps) to my i3 desktop. However trying another machine on Windows 10 (AMD Athlon II X4 645, Geforce 650, 16GB RAM) (All using OpenGL for comparison). I'm getting a near solid 60fps the odd dip to 50 here and there but nothing like I'm seeing on Linux. As far as I know the i3 and i5 CPU's should be much better performers than the AMD, likewise the 660ti should wipe the floor with the 650.

So I guess I'm missing something here as far as configuring / running the Linux port? Any suggestions?

[degasus]

The "threaded optimization" of the nvidia driver is disabled by default on linux, but enabled by default on windows. Try: __GL_THREADED_OPTIMIZATIONS=1 as environment variable.

The performance of windows and linux should be very similiar else.

[_c0rr0si0n_]

Thanks degasus, that certainly helped improve things. Frame rates appear to be 7-10 FPS up on where they were however it seems I'm still far off my other Windows test box. Are there any other optimization flags or environment variables I could try passing in?

[leolam]

Which thread is using 100% of CPU time? Is it the GPU thread?

(you can see that fairly easily with htop, and showing custom thread names.)

[_c0rr0si0n_]

During the opening video / title / menu screen CPU thread 100% Video thread ~8%
In game during a 40-45 FPS section CPU thread is sat at 100% Video at ~55%
On the pause screen CPU thread at 80-90% and Video thread still at around 50%

[leolam]

100% CPU usage on the CPU thread doesn't sound normal at all.

1) Make sure you are running the latest development version.
2) Reset your Dolphin configuration by deleting ~/.dolphin-emu (warning: this will remove your Wii NAND too) or ~/.config/dolphin-emu and see if the issue still happens with the default settings.

[_c0rr0si0n_]

So I've tried the Dolphin PPA and the Appimage (https://forums.dolphin-emu.org/Thread-dolphin-as-appimage-on-linux) version of Dolphin.

I've removed both ~/.dolphin-emu and ~/.config/dolphin-emu unfortunately the issue persists. Any suggestions on what I can try next?

Many thanks for your on going help.