AMD's Catalyst A.I. Is Good For Few Linux Games

[phoronix]

Phoronix: AMD's Catalyst A.I. Is Good For Few Linux Games

Catalyst A.I. is a feature built into AMD's proprietary Radeon graphics driver meant to enhance the OpenGL performance for certain games, but under Linux it's not incredibly useful...

http://www.phoronix.com/vr.php?view=MTI1ODM

[Sidicas]

Obligatory Anandtech explanation on Catalyst AI:
http://www.anandtech.com/show/1488/2

The summary of that is basically...
Catalyst AI = Finding ways to take shortcuts that have the most minimal impact on image quality for rather large boosts in performance.

So from my understanding, the applications that benefit the biggest from Catalyst AI are games that are most poorly optimized for running on AMD's graphics hardware.

So in theory, seeing performance boosts by using Catalyst AI is *BAD* as it means you should go back and change your game to make it run better on AMD hardware.

Not seeing any performance boosts from using Catalyst AI on linux games is in fact, a good thing, as it means the games already are optimized "reasonably" for AMD hardware.

[Detructor]

Obligatory Anandtech explanation on Catalyst AI:
http://www.anandtech.com/show/1488/2

The summary or that is basically...
Catalyst AI = Finding ways to take shortcuts that have the most minimal impact on image quality for rather large boosts in performance.

So from my understanding, the applications that benefit the biggest from Catalyst AI are games that are most poorly optimized for running on AMD's graphics hardware.

So in theory, seeing performance boosts by using Catalyst AI is *BAD* as it means you should go back and change your game to make it run better on AMD hardware.

Not seeing any performance boosts from using Catalyst AI on linux games is in fact, a good thing as it means the games already are optimized well for AMD hardware.

I'm not sure if there is such a great difference between how Nvidia handles OpenGL and how AMD handles OpenGL. Meaning: Bad code is bad code and is slow on any machine.

[przemoli]

I'm not sure if there is such a great difference between how Nvidia handles OpenGL and how AMD handles OpenGL. Meaning: Bad code is bad code and is slow on any machine.

There is lots of differences. Hardware is different. Software part (drivers) is also different, and markets are slightly different (NV Cuda and GPGPU lead).

So yes ONE code can run with various performance on comparable cards from different vendors, while changing that code to do exactly same thing but by other means can change that disparity.

And lets not forget bugs. And perf bugs. Both companies release new drivers with better and better perf. So both vendors create suboptimal GPUs (both in hw and sw). Something we can expect in not quite perfect world

[Detructor]

There is lots of differences. Hardware is different. Software part (drivers) is also different, and markets are slightly different (NV Cuda and GPGPU lead).

So yes ONE code can run with various performance on comparable cards from different vendors, while changing that code to do exactly same thing but by other means can change that disparity.

And lets not forget bugs. And perf bugs. Both companies release new drivers with better and better perf. So both vendors create suboptimal GPUs (both in hw and sw). Something we can expect in not quite perfect world

thanks for the info.

[Morpheus]

The code optimization on the app side is a better way to go : I just tested Serious Sam 3 (Steam FTW), using the "stable" version results in various lags and far worse performance than on windows (same settings). Let's put the publicbeta in place : runs almost as smooth, still some glitches on shadows, but far far better. Same OS, same drivers (old, as Steam warns me), but definitely good to the eye for me.

Catalyst AI is only relevant with games AMD choose to analyse and optimize driver side : only Doom 3 see a real FPS boost, obviously as it is a commercial game (yes, i know it has been opened since). So on this case, Michael's previous statement on "Catalyst AI useless" still sounds good, as I don't see AMD look at various open-source games and find a way to "enhance" them.

[smitty3268]

Not seeing any performance boosts from using Catalyst AI on linux games is in fact, a good thing, as it means the games already are optimized "reasonably" for AMD hardware.

A lot of the games Michael tests don't really have any shaders in them anyway, and i don't think Catalyst A.I. would do anything for them regardless of how well optimized they are.

[Redshirt001]

I'd like to know if this Catalyst AI has any impact on performance when using games via WINE.

[Morpheus]

Usually, Catalyst AI analyzes directly commands straight from the game to see if it can be "optimized". As Wine translates the commands into OpenGL before passing it to the driver, I'm not sure it's working anymore. Unless I'm wrong with the way Wine works, but I believed DirextX support did not exists in linux drivers (mostly kernel related features, as we can see on MSFT postings on the subject).

[Redshirt001]

Usually, Catalyst AI analyzes directly commands straight from the game to see if it can be "optimized". As Wine translates the commands into OpenGL before passing it to the driver, I'm not sure it's working anymore. Unless I'm wrong with the way Wine works, but I believed DirextX support did not exists in linux drivers (mostly kernel related features, as we can see on MSFT postings on the subject).

You might be right, but I guess I thought there might be a chance the Catalyst AI would have some effect, considering you can force AA through the Nvidia control panel, for instance. Can't count on it, obviously.