Debugging graphics performance in a simple and high-level manner is possible for all Gallium based Mesa drivers.

GALLIUM_HUD

GALLIUM_HUD is a feature that adds performance graphs to applications that describe various aspects like FPS, CPU usage, etc in realtime.

It is enabled using an environment variable, GALLIUM_HUD, that can be set for GL/EGL/etc applications. It only works for Mesa drivers that are Gallium based, which means that the most drivers (with the notable exception of some Intel drivers) support GALLIUM_HUD.

See GALLIUM_HUD options:

export GALLIUM_HUD=help
glxgears

Android

If you're building Android, you can supply system-wide environment values by doing an export in the init.rc file of the device you are using, like this.

# Go to android source code checkout
cd android

# Add export to init.rc (linaro/generic is the device I use)
nano device/linaro/generic/init.rc
export GALLIUM_HUD cpu,cpu0+cpu1+cpu2+cpu3;pixels-rendered,fps,primitives-generated

Linux

If you're using one of the usual Linux distros, GALLIUM_HUD can be enabled by setting the environtment variable in a place that it loaded early.

# Add export to /etc/environment
nano /etc/environment 
export GALLIUM_HUD cpu,cpu0+cpu1+cpu2+cpu3;pixels-rendered,fps,primitives-generated

Thanks

This post has been a part of work undertaken by my employer Collabora.

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