[2.0.60] MacOS Metal Graphics backend 48.0 FPS

[Jakoski360]

Updated from 2.0.55 to 2.0.60, Factorio now runs at a locked 48.0 FPS & 60.0 UPS when the Metal (experimental) backend is used. This occurs on both Singleplayer and Multiplayer.

This behaviour was not experienced with the previous release 2.0.55, FPS and UPS were both 60.0 while using Metal (experimental).
UPS is not affected, and using OpenGL backend works fine.

Log reports uploaded:
factorio-previous - OpenGL backend, FPS/UPS: 60.0/60.0
factorio-current - Metal (experimental) backend, FPS/UPS: 48.0/60.0

Macbook Pro 2024, M4 Pro, monitor is configured at 144Hz.

[Loewchen]

Post debug screenshots as described in 68653 please, and if the issue is not present on a brand new map a save that shows the issue.

[Jakoski360]

Screenshots, save file and latest log file attached.

[Jakoski360]

I have done some more testing as I noticed that Vsync was impacting my performance on OpenGL. Looking at the difference between Flip[on] (Vsync On) and Flip[off] (Vsync Off) time usage on the debug screen, I checked to see if Vsync was causing the issue on Metal. Vsync did not affect this issue on Metal but I did find some possibly useful information.

OpenGL:
Flip[on] - Max 19, Min 3
Flip[off] - Max 2, Min 0.4

Metal:
Flip[on] - 19
Flip[off] - 19
Changing Vsync settings while using Metal does not seem to affect the time usage of Flip in the same way that it does when using OpenGL.

Please let me know if there is any more information I can provide.

[Rseding91]

If you set the monitor to 60hz how does it perform?

[Jakoski360]

Changing refresh rate to 60Hz resolves the issue on Metal, game runs at 60 FPS.

120Hz also seems OK, game runs at 60 FPS.

Interestingly if I set the monitor to 95Hz, the game runs at 47.5 FPS. Seems for some reason since this update the game is running at fractions of the monitor refresh rate.

I have not tested any of the releases between 2.0.55 and 2.0.60 so I cannot say exactly when this was introduced.

If it makes any difference, the resolution is 3840x2160 across all of these tests, fullscreen.

[Rseding91]

That sounds similar to FPS dropping to 30 with vsync when overloaded because the game tries to update at 60 FPS but when it finishes an update it missed the screen refresh window and had to wait for the next one.

[Jakoski360]

Yeah at first I thought it could be vsync related, but those last tests were done with vsync off. I tried in a new sandbox save with UPS uncapped and got the same results as my original screenshots (~3800 UPS but FPS locked at fractions of monitor refresh rate).

[badosz]

I'm having exact same problem with Metal on 2.0.60 (didn't on earlier versions), going back to OpenGL fixes fps issue.