Open-Source Raspberry Pi Graphics Drivers Add Double Buffer Mode

[coder]

How could it be that any aged, entry level, Intel or AMD processor (10 years) with integrated graphics, outperforms it in simple tasks like running GNOME or KDE desktop compositor effects, or video playing, when the Raspberry has supposedly more modern graphics hardware?

The Pi is made to be cheap, above all else. That means it was made on an old process node (28 nm) and they didn't devote much die space for the GPU portion. And even though it runs hot, it still burns like 0.15x as much power as those old AMD and Intel CPUs (which were made on similar manufacturing nodes, BTW).

Also, as others have mentioned, the memory datapath is only 32-bits, instead of the 128-bit path in modern CPUs. This means it has only about 13 GB/sec, whereas a 10-year-old Intel or AMD CPU would have almost 2x as much memory bandwidth.

And I don't understand how this machine was announced as capable of 4K video playback.

That depends on a hardware video decode block. You have to make sure it's working properly in whatever player you're trying to use.

[DebianLinuxero]

Yeah, but its width is 32 bit. On x86 a single channel is 64 bit, and you get 128 bit in dual-channel mode.

I want to point that my first comparison is with 10 year x86 processors.
At that time, the most common memory type was DDR3.
So we are comparing DDR4 with DDR3. Now we are halving the bandwidth.

And even a cheap built machine, that ones that were populated with only one memory DIMM, were more capable to run smooth the GNOME desktop effects, the transitions, the scalar effects, and so on.

I think Igalia is doing a well job.
And think the hardware is capable of a rather normal desktop experience at 1080P, even at 2K.

My blame is more for Raspberry PI foundation.
You can't sell a device without proper support.

[anarsoul]

Pi 400 has LPDDR4-3200, didn't check Pi 4, likely the same.

Yeah, but its width is 32 bit. On x86 a single channel is 64 bit, and you get 128 bit in dual-channel mode.

[TheOne]

I have a Raspberry PI 4b 4GB.
I don't talk about games. I talk about simple desktop use.

And I don't understand how this machine was announced as capable of 4K video playback.

One of the reasons for poor video playback performance as far as I know is that the hardware video decoder kernel drivers + user space to use it are lacking, hardware vendors care more for Android than mainline Linux... on the 3D/2D side, the mesa drivers need more optimizations. Lastly thermals, the RPI if used for more heavy tasks as desktop usage would need a cooling solution to keep it from throttling because excessive heat will downclock your CPU making the system feel sluggish.

[unic0rn]

I have a Raspberry PI 4b 4GB.

I thought it was a good idea but graphics performance in 64 bit mode is disappointing.

How could it be that any aged, entry level, Intel or AMD processor (10 years) with integrated graphics, outperforms it in simple tasks like running GNOME or KDE desktop compositor effects, or video playing, when the Raspberry has supposedly more modern graphics hardware?

I don't talk about games. I talk about simple desktop use.

And I don't understand how this machine was announced as capable of 4K video playback.

it's capable of 4k video playback using OpenELEC. everything else - in case of problems, blame the drivers/other software.

in case of poor desktop performance - blame the drivers.

have you tried manjaro gnome running on wayland? i'm asking because i'm considering getting Pi 400 myself.

Oh, that's easy. Most of modern ARM SBCs have a fraction of memory bandwidth of 10yo x86 systems.

Pi 400 has LPDDR4-3200, didn't check Pi 4, likely the same.

[anarsoul]

How could it be that any aged, entry level, Intel or AMD processor (10 years) with integrated graphics, outperforms it in simple tasks like running GNOME or KDE desktop compositor effects, or video playing, when the Raspberry has supposedly more modern graphics hardware?

Oh, that's easy. Most of modern ARM SBCs have a fraction of memory bandwidth of 10yo x86 systems.

[tildearrow]

Why do you expect high performance from a cumputer that can run off of a 15W power supply?

Because Apple did it.
The Mac mini only consumes 30W while having similar single-thread performance as a 9900K.

As much as I hate saying that...

[dlq84]

Why do you expect high performance from a cumputer that can run off of a 15W power supply?

[dragorth]

I have a Raspberry PI 4b 4GB.

I thought it was a good idea but graphics performance in 64 bit mode is disappointing.

How could it be that any aged, entry level, Intel or AMD processor (10 years) with integrated graphics, outperforms it in simple tasks like running GNOME or KDE desktop compositor effects, or video playing, when the Raspberry has supposedly more modern graphics hardware?

I don't talk about games. I talk about simple desktop use.
r
And I don't understand how this machine was announced as capable of 4K video playback.

Simply put, those processors are runnint at 2Ghz+while with lots of power room while the Pi is not. So, the AMD and Intel have lots of legacy and other hardware dedicated to those use cases, while the Pi GPUs are very lean to conserve power and cost.

[tildearrow]

I have a Raspberry PI 4b 4GB.

I thought it was a good idea but graphics performance in 64 bit mode is disappointing.

How could it be that any aged, entry level, Intel or AMD processor (10 years) with integrated graphics, outperforms it in simple tasks like running GNOME or KDE desktop compositor effects, or video playing, when the Raspberry has supposedly more modern graphics hardware?

I don't talk about games. I talk about simple desktop use.

And I don't understand how this machine was announced as capable of 4K video playback.

I agree with you.
Most ARM designs have rather poor performance, unless it's from Apple or Ampere.
I honestly was surprised to see that a Raspberry Pi was only as fast as my Phenom...