best way to monitor framerate with drm?

[jvcleave]

I am writing a drm based app and I seem to be capped at 30fps even though my drmModeModeInfo refresh returns 60fps


I am looking for something like this

https://wiki.st.com/stm32mpu/wiki/DRM_K ... _framerate

[6by9]

From that ST page you link to

The DRM/KMS framework does not offer natively a display framerate monitoring, the above solution is powered by the STMicroelectronics DRM/KMS implementation.

https://github.com/raspberrypi/linux/bl ... tdc.c#L885 is presumably the logging lines they are looking at. That's the number of updates per plane, not per display. You could add a similar thing to vc4 - PRs welcome.

[jvcleave]

Thanks! Is it odd that I don't get 60fps with kmscube in legacy mode? I've even reduced the drawing to just glClear

[6by9]

Thanks! Is it odd that I don't get 60fps with kmscube in legacy mode? I've even reduced the drawing to just glClear

Pi4 or Pi3?
If Pi4 then you've dropped back to software GL, and that will be slow.

[jvcleave]

It's a PI4 (X not running)

OpenGL ES 2.x information:
version: "OpenGL ES 3.0 Mesa 19.2.0-rc1"
shading language version: "OpenGL ES GLSL ES 3.00"
vendor: "Broadcom"
renderer: "V3D 4.2"

[jvcleave]

not sure what but something with kmscube is different than this similar implementation that runs at 60fps

https://github.com/matusnovak/rpi-opengl-without-x

[Gavinmc42]

With two screens, could the other be used as debug output, ie fps etc.
Can piglet be used?
I am so far down the learning curve I am on flat ground, I have to use things like this for inspiration.
https://www.iquilezles.org/www/index.htm

Godot4 will have a CPU/GPU profiler, that will be useful one day.