[chao-]

They were referencing a time, in the middle of the 2010's, when "amdgpu" was released. It is a completely rewritten, different driver, and is mostly open source [0]. Before that, the driver was named "radeon" and it was very shaky. I can speak to this personally. I had desktop Linux systems with both AMD/ATI and Nvidia GPUs, and while there were some issues with Nvidia, the AMD/ATI drivers gave me nightmares.

Once the rewritten "amdgpu" driver came out, things got much better. The first few cards created after that (IIRC the Polaris GPUs, RX 400's), the situation reversed. I still have had occasional issues with various Nvidia cards (normally driver updates breaking things), but for almost a decade now, I have not had issues with AMD GPUs under Linux.

[0] Except for pro features while using workstation cards. You need to use a proprietary driver for those, but even those share a lot of code with the open source driver.

[trws]

You have this largely right, but I need to defend the Radeon driver a bit here. The driver that caused all the problems was the proprietary fglrx driver, not the open source Radeon driver. The issue with the Radeon driver wasn’t stability, it was that it was 2d acceleration only.

[tremon]

it was 2d acceleration only

Not completely true either, it eventually supported most of the normal 3d primitives but gaming performance was never a priority because there were few developers and they weren't employed by AMD/ATI -- which also meant that some cards would only reach full feature support after their EOL, sadly.

The amdgpu also driver benefits from a lot of the groundwork that has been done since. The radeon driver is older than kernel features like KMS (kernel modesetting) and GEM (graphics execution manager), and the LLVM-based shader compiler in mesa (userspace). I'd say that the radeon driver was actually the proving ground for many of these features, because it was the most capable open source 3d driver: The Intel 845/915 hardware barely supported 3d operations, and the only 3d-capable open source driver for Nvidia was the reverse-engineered nouveau driver.

Luckily, many people working on the amdgpu driver are actually on AMD's payroll these days.

[account42]

AMD had developers working on radeon (the older open source kernel driver) and radeonsi (the open source user-space OpenGL driver backend for newer cards in Mesa that now sits on top of amdgpu) before the switch to amdgpu (the newer open source kernel driver). While the kernel driver isn't irrelevant for performance, it depends more on the user space portion (radeonsi and r600 before that) which was kept with the amdgpu switch. What the amdgpu driver brought is more sharing of display code with their windows drivers. The main difference in performance is between r600 (mostly developed without financial support from AMD) and radeonsi (mostly developed by AMD). Of course these days the most relevant user-space portion is radv (open source Vulkan driver in Mesa) which is NOT developed by AMD but rather funded by Valve (and at least initially Red Hat). There is also the open source amdvlk Vulkan user-space driver developed by AMD which is the same as their proprietary Vulkan driver except with the proprietary shader compiler swapped out for the same LLVM backend that radeonsi uses. And if this all wasn't confusing enough, AMD also calls the full driver package with the proprietary Vulkan driver and some snapshot of the open source OpenGL Mesa drivers (radeonsi) "amdgpu-pro".

[chao-]

I remember! I stand corrected on the name and the issues!

I forgot that name "fglrx", probably a mental self-defense mechanism. Those were some bad times, trying to get different display outputs to work at the same time, guessing and testing values in xorg.conf, so on. There was some community utility someone wrote to try and help with installation, reinstallation, configuration and reconfiguration, but the name eludes me now.

I would edit my post to correct it, but it seems the edit window has passed.

[microtonal]

The first few cards created after that (IIRC the Polaris GPUs, RX 400's)

Even Sea Islands/Southern Islands were much better with amdgpu (but you have to use a module parameter to enable support).

[pjmlp]

And with that release, my ASUS 1215B was downgraded from OpenGL 4.1 into OpenGL 3.3, it took several years for the open source driver to catch up in features to the old closed source driver, and when it finally did, my netbook was at the end of its life.

Ah and hardware video decoding never ever worked again.

So much for the so called advantages of an open source driver.

[bsimpson]

That's high praise - props to the people who worked on that rewrite!