Is it possible to speed up GBA link?

[v1993]

So I've been trying to play FSA with VBA-M to dump multiplayer-exclusive textures and noticed big slowdown on 3-4 GBAs (using VBA-M) connected.

I tried:

• Disabling V-Sync everywhere. Seems to have little effect.
• Using 50FPS mode. Makes music a lot better, gameplay still lags.
• Rebuilding everything with max optimizations (`-march=native -O3` for dolphin and `-march=native -Ofast` for VBA-M). Made 2-player play near perfect, but still big lags heavily on 4 players.
• Enabling speed hack in options menu. Seems to improve situation a bit (+2-3 FPS), but not too much.
• Using clock override in dolphin. Makes game run smoothly but makes it slow to unplayable levels. Had to disable
• Turning on "Turbo mode" in VBA-M. Makes emulation run nearly perfect (little frame drops happen, but it is more than playable), but GBA picture lags instead, making it nearly unplayable when GBA screen is used. Disabled in the end due to this.
• Disabling video filter and interpolation in VBA-M. Improved situation a bit (+5-7 FPS or so), but still lags are present.
• Changing video quality options in Dolphin. Reduced picture quality, but that's it, no FPS improvements. Resorted to original ones.
  

In the end, game plays at 37-50 FPS (in 50FPS mode) with a bit visible slowdown but music and sound problems are easy to hear.

Is there anything else I can try to improve performance? All emulators are run locally on two screens (one for dolphin and other for all four VBA-M windows).

P.S.: is there an easy way to make each VBA-M use different control scheme? I currently have to go and select "Use by default" for needed input profile for each window I open. Is it correct that I have to start VBA-M manually for each player?

I'm using latest git dolphin and VBA-M.

[KHg8m3r]

If you can handle the game not being fullspeed, have you tried enabling audio stretching (Config > Audio >Audio Stretching)? May help with making it sound less horrible

[v1993]

(03-14-2020, 02:08 PM)KHg8m3r Wrote: If you can handle the game not being fullspeed, have you tried enabling audio stretching (Config > Audio >Audio Stretching)? May help with making it sound less horrible

Thanks for suggestion, but I already have it enabled and it still have gaps in resulting audio. I guess setting emulation speed to 80-90% might help with this (should probably try), but improving speed is obviously preferable.

[mstreurman]

(03-14-2020, 09:44 PM)v1993 Wrote: Thanks for suggestion, but I already have it enabled and it still have gaps in resulting audio. I guess setting emulation speed to 80-90% might help with this (should probably try), but improving speed is obviously preferable.

My guess is that the CPU is struggling to run all these instances of emulators at the same time, although I haven't tried to set this up on my system yet. Can you tell us what "top" is telling you what your CPU usage is when running all these systems?

[v1993]

(03-15-2020, 06:13 AM)mstreurman Wrote: My guess is that the CPU is struggling to run all these instances of emulators at the same time, although I haven't tried to set this up on my system yet. Can you tell us what "top" is telling you what your CPU usage is when running all these systems?

Can't run this setup now, but I remember CPU usage being high but not 100%. Shouldn't turbo mode actually make it worse?

[skid]

Turbo mode removes the wait states from the emulation and that is why it goes faster.