Severe lag during tutorial in Armored Core 4 when WCB is enabled on Fedora

[karmazogs]

Quick summary

When "Write Color Buffers" is enabled, upon reaching the second phase of the tutorial and turning around after the first test, the game drops from ~60 fps to ~20-30 fps. This doesn't seem to be a bottleneck as CPU usage is normal during the frame drops.

Details

No response

Attach a log file

RPCS3.log.gz

Attach capture files for visual issues

ac4 tutorial lag.tar.gz

System configuration

OS: Fedora 40
CPU: AMD Ryzen 5 5600X
GPU: AMD Radeon RX 6700 XT
RAM: 16 GB

Other details

No response

[AniLeo]

Can you post the full performance overlay from both Write Color Buffers ON and OFF on the same scene? To have a proper performance comparison. As well as using uncapped FPS, to not be limited at 60.

[karmazogs]

Can you post the full performance overlay from both Write Color Buffers ON and OFF on the same scene? To have a proper performance comparison. As well as using uncapped FPS, to not be limited at 60.

The game does not like uncapped framerates one bit

WCB on

WCB off

[kd-11]

Enable the full dev overlay in the config file by setting "Debug Overlay" option to true. You can also find this on the debug tab if you have it enabled. A lot of text will appear on the top left of the screen with some internal stats.
That said, poor WCB performance on linux is expected though I've never seen it this severe. The real root cause is this: https://gitlab.freedesktop.org/mesa/drm/-/issues/89

[karmazogs]

Enable the full dev overlay in the config file by setting "Debug Overlay" option to true. You can also find this on the debug tab if you have it enabled. A lot of text will appear on the top left of the screen with some internal stats. That said, poor WCB performance on linux is expected though I've never seen it this severe. The real root cause is this: https://gitlab.freedesktop.org/mesa/drm/-/issues/89

WCB on

WCB off, framelimit 60

WCB off, framelimit off

[kd-11]

While I see WCB introducing overhead it really shouldn't be this bad. Are you using the GPU for anything else in parallel? I can capture some RGP profiles later but that will take time as I'm busy with other tasks.

[karmazogs]

While I see WCB introducing overhead it really shouldn't be this bad. Are you using the GPU for anything else in parallel? I can capture some RGP profiles later but that will take time as I'm busy with other tasks.

Usually just Youtube and Discord I think.

[karmazogs]

Also I should've specified I'm on the KDE Plasma spin of Fedora 40 if that's relevant at all. Asking around in other places someone mentioned offhand that it could be Wayland causing the issue? I'm not smart enough to figure any of this out on my own and I just want to know if it's something I did or something I can fix.

[atlrvrse]

I'm experiencing the same problems in For Answer too