Dolphin uses ffmpeg to play / show the videos of the games?

[Darumo]

Dolphin uses ffmpeg to play / show the videos of the games?

I have a problem and it is that Archlinux 64bit are very bad performance, only the videos in the games. It's something that happened to me with Archlinux 64bit and it did not happen on Kubuntu 16.04 64bit. And I'm looking at what might be due to that.


They are stretched to 16: 9, with the image unfiltered and the performance drops exaggeratedly.



Archlinux 64bit
i5 2500K 4.6ghz
16gb DDR3
Nvidia GTX 1080 (drivers 375.10)
FFmpeg 3.2

[JosJuice]

No, Dolphin doesn't use FFmpeg to decode anything. The video decoder is part of the game's code, and Dolphin emulates it the same way it emulates any other GC/Wii code.

[Darumo]

Can it be because of the continuous loading of textures to the graphics card? During the videos the emulator seems to upload a texture for each video image. I do not know if it is a bug in the Nvidia driver if it were that upload of textures to the graphics card that caused the slowdowns.

[nano351]

I've been noticing a similar regression (slowdown in FMV sequences), however i'm unsure how to debug it

[leolam]

"regression" implies you found a last "good" version, and a first "bad" version. What is the first version where it starts happening?

[JMC47]

I've also noticed that FMVs are unreasonably slow... but only in Linux. What's going on?

[nano351]

(11-26-2016, 03:44 AM)leolam Wrote: "regression" implies you found a last "good" version, and a first "bad" version. What is the first version where it starts happening?

my data points so far are just that the current build I have 5.0-1339 has the performance issue, but I don't recall what the version of the previous one was which didn't have it. I'll try testing some older versions to see if I can pinpoint.

[leolam]

Since you're on Linux, you can use git bisect to bisect pretty efficiently and reduce the number of versions you have to test.

[nano351]

(11-27-2016, 02:17 AM)leolam Wrote: Since you're on Linux, you can use git bisect to bisect pretty efficiently and reduce the number of versions you have to test.

Seems the issue is actually something outside of Dolphin. I went back to a commit before 5.0 and was still seeing the same slowdown on my system and I know it was working fine past 5.0.. seems to be CPU bound since the slowdown happens even when null renderer is enabled and a single core of the CPU is maxing out. I'm using melee to test, the intro video has been running at 40 fps using JIT64 DC or SC. JITIL64 is able to run the intro video at 60fps but is too unstable to actually use.

[nano351]

For anyone who stumbles upon this thread later, the source of the issue was mentioned in a recent blog post. The problem is from a bug in glibc: https://dolphin-emu.org/blog/2016/12/01/dolphin-progress-report-november-2016/

I had updated from ubuntu 14.04 -> 16.04 and compiled the latest dolphin source, and hadn't realized it could have been from a system library.