Linux 2.6.34 Kernel Released! Time For 2.6.35

[RealNC]

I have an R770 (HD4870). There is heavy lag when scrolling in every application (especially Gtk apps, and to a lesser extent Qt apps), some lag when pressing F12 to show my Yakuake console, video playback with Xv is skippy, navigating menus in application is laggy, lag when restoring windows from their minimized state (and that one turns even more laggy if another window is currently open rather than a clear desktop.)

All combined, it feels like Windows 7 on a Pentium 3 :P

[Loris]

I have an R770 (HD4870). There is heavy lag when scrolling in every application (especially Gtk apps, and to a lesser extent Qt apps), some lag when pressing F12 to show my Yakuake console, video playback with Xv is skippy, navigating menus in application is laggy, lag when restoring windows from their minimized state (and that one turns even more laggy if another window is currently open rather than a clear desktop.)

All combined, it feels like Windows 7 on a Pentium 3 :P

OpenGL compositing?

[RealNC]

Yes .

[Loris]

Yes .

Sorry, but, are you complaining (with whom?) because you really thought that the old Mesa OpenGL model driver for r600+ was already done, optimized and all? By the time I'm seeing your nickname here on Phoronix, I thought you would have already knew: we'll start to see something only when the Mesa Gallium3D driver for r600+ will begin to be seriously worked upon. Jerome Glisse did the original work, Marek Ol??k updated the code to current Mesa.

http://www.phoronix.com/scan.php?page=news_item&px=ODIzMw

But, you already know this.

What did you expect that you didn't know already? Really.


PS: If you experience tearing in a composited environment, that's because kernel code for the query of crtc hw id as been merged mainline just yesterday, while the xf86-video-ati already has swap & sync code since 10 May.

If you're interested:
kernel commit: bc35afdb182d4c48c889fe27ba7a5d7ea0c8194d

[RealNC]

What does this have to do with UMS vs KMS?

[Loris]

You made four observations to the KMS stack on your hardware:

• KMS has DRM powermanagement, which works on your hardware.
  Further advancements in DRM PM will only be available in KMS (profile-based and dynamic PM).
• X-Video tearing, which is solved by synchronized swap in 2.6.35 KMS DRM.
• OpenGL tearing, which is solved by synchronized swap
• OpenGL performance, which can only be solved by further r600g development.

What does this have to do with UMS vs KMS?

This.

[RealNC]

You don't make any sense, sorry. I never mentioned anything about vsync problems in Xv; there are none. I never said my desktop was tearing; it doesn't. I never said power management didn't work; it does work. I don't understand why gallium is needed for faster KMS performance; all I'm saying is KMS is slower than UMS.

So I'm gonna write it again:

I have an R770 (HD4870). There is heavy lag when scrolling in every application (especially Gtk apps, and to a lesser extent Qt apps), some lag when pressing F12 to show my Yakuake console, video playback with Xv is skippy, navigating menus in application is laggy, lag when restoring windows from their minimized state (and that one turns even more laggy if another window is currently open rather than a clear desktop.)

All combined, it feels like Windows 7 on a Pentium 3 :P

[Loris]

You don't make any sense, sorry.

Wow.

I never mentioned anything about vsync problems in Xv; there are none.

That's what DRI2 wich is available in KMS is for. You told us that the UMS stack gave you tearing issues.

I never said my desktop was tearing; it doesn't. I never said power management didn't work; it does work.

As I stated already, you did bring up four observations, some of which are issues, some are not. You already told us that DRM power management works well, and I'm pleased to hear that.

I don't understand why gallium is needed for faster KMS performance; all I'm saying is KMS is slower than UMS.

There isn't a "KMS performance", there's a legacy Mesa driver performance. That's why your "GTK scrolling" is lagging, and showing a new window (Yakuake) does take time: the legacy Mesa driver for r600 has just been put together, it's not feature complete or even nearly optimized (except things like DMA swapping).

We can't talk of "KMS", wrapping up a DRM kernel module, Xorg server, Xorg DDX, and a Mesa driver. We have to distinguish each component, for each has its function and development.

If you need an OpenGL composited desktop, than you'll need good performance from your OpenGL implementation. That's what Mesa and Gallium3D are. Mesa's r600 driver isn't and will not be optimized further, but Gallium's will. Even more: Mesa UMS and KMS r600 drivers are different code paths, because they are a very different approach to similar problems.

Gallium is where a great deal of the current, and all future development (new features, performance improvements, ...), will take place. So that's why you should be looking at G3D.

Do I make any sense?

[bwat47]

I have an R770 (HD4870). There is heavy lag when scrolling in every application (especially Gtk apps, and to a lesser extent Qt apps), some lag when pressing F12 to show my Yakuake console, video playback with Xv is skippy, navigating menus in application is laggy, lag when restoring windows from their minimized state (and that one turns even more laggy if another window is currently open rather than a clear desktop.)

All combined, it feels like Windows 7 on a Pentium 3 :P

I am using kms with a 4870 and a mobility 2600. I have used ubuntu with 2.6.32, 2.6.34 (rc5-final) and arch linux with 2.6.34 drm-radeon-testing. On all of these speed is no issue, the oss drivers with kms are significantly faster than cat 10.4. Video playback is perfectly smooth even on my laptop (2ghz core2, mobility 2600)

My only issue is the temps on my laptop get REALLY hot with the oss drivers even with dynpm enabled.

[RealNC]

I'm so happy for you.