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Raspberry PI 4 Model B and hardware graphics acceleration

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Have you seen these free online magazines all about using and getting the most from the RPI  ..

I know about overclocking, but I don't want to do it, because it requires overvoltage and as result it may lead to chip damage or quick degradation. And of course it will increase heating, but it is already too hot.

Regarding to heating, I tried to add 12 mm silent fan from PC case, it easily cool down CPU below 40 °C even under heavy load. But its preferred for me to keep it fan less and noise free... :)

As I read, the BCM2711 CPU doesn't have hardware cryptographic acceleration, it seems that they forgot to add license for hardware AES instruction when designed chip. So all cryptography eats a lot of CPU and add heating, and since these days TLS cryptography is everywhere (any HTTPS connection requires it, SSH and VNC, disk encryption and many other things), it leads to additional significant CPU load and heating.

It looks that they tried to improve situation by enable NEON acceleartion support in openssl, but it just improve performance for a little, it can't replace hardware cryptography acceleration instructions which give 10-20x speed improvement.

Since VNC uses AES encryption, it seems that it may affect CPU load. So, I'm waiting for hdmi cable and adapter to test it on real display...

Just got hdmi adapter and connected my RPI4 to display :) It works much more smoothly than through VNC. But I found another issue related with vblank sync. All video playback and OpenGL app shows image tearing due to delayed frame swap from vblank event. It looks terrible. But I found it can be fixed with disable Compositor (xcompmgr) from raspi-config (on Advanced menu). With disabled xcompmgr image tearing disappears and vblank sync works as expected.

glxgears test shows about 990-1000 fps with enabled xcompmgr and about 1450 fps with disabled xcompmgr, so disable xcompmgr also improves OpenGL performance:

--- Code: ---$ vblank_mode=0 glxgears
ATTENTION: default value of option vblank_mode overridden by environment.
7029 frames in 5.0 seconds = 1405.637 FPS
7296 frames in 5.0 seconds = 1459.048 FPS
7317 frames in 5.0 seconds = 1463.390 FPS
7357 frames in 5.0 seconds = 1471.392 FPS
7302 frames in 5.0 seconds = 1460.214 FPS
7287 frames in 5.0 seconds = 1457.341 FPS
7261 frames in 5.0 seconds = 1452.113 FPS

--- End code ---

Any further ideas to improve OpenGL performance are welcome. I want to see for at least 2000-3000 fps in glxgears


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