Bug 30606

does xf86-video-ati 6.12.2 or git master work any better?

I already use xorg-edgers, so i think that is close to git master.

I tried the r300 classis radeon driver, same results. 

Is xf86-video-ati the same as the radeon driver? or is it a different driver?

(In reply to comment #2)
> Is xf86-video-ati the same as the radeon driver? or is it a different driver?

Same driver.

As far as I know chromium only does client-side rendering and then uploads the software-rendered contents using either SHMPutImage or SHMPixmaps.

I also see slow scrolling compared to Firefox on my i945GM laptop + a 1920x1200 display - but I guess that can be simply attributed to the huge amounts of data copied arround.

(In reply to comment #4)
> As far as I know chromium only does client-side rendering and then uploads the
> software-rendered contents using either SHMPutImage or SHMPixmaps.
> 
> I also see slow scrolling compared to Firefox on my i945GM laptop + a 1920x1200
> display - but I guess that can be simply attributed to the huge amounts of data
> copied arround.

So this is a problem in the design of chromium? 

However, the windows versie is very fast with scrolling, so why is it fast on windows and slow on ubuntu?

Just FYI, this might give you some hints:

http://code.google.com/p/chromium/issues/detail?id=28544

(In reply to comment #6)
> Just FYI, this might give you some hints:
> 
> http://code.google.com/p/chromium/issues/detail?id=28544

Thanks for the info, so it is up to the developers of chromium ...

well, the question is why radeon is slow in thase case for (SHM)PutImage.

(In reply to comment #8)
> well, the question is why radeon is slow in thase case for (SHM)PutImage.

Is it really only doing SHM PutImage stuff?   I've got a bug where I can reliably trigger [drm:radeon_cs_ioctl] *ERROR* Failed to parse relocation -12! from just scrolling around and zooming  in Google Maps on Chrome (chromium browser daily builds on Maverick).   While I can reliably trigger this (every time) in KDE with Desktop effects, I have also managed to trigger it on Gnome with out desktop effects.

If Chromium was only using PutImage would it really trigger stuff like that from drm?

Dave

> If Chromium was only using PutImage would it really trigger stuff like that
> from drm?

Just gave it a try - on intel/uxa where ShmPixmaps are supported it mostly does:
- CreateShmPixmap
- XRenerComposite
- XFreePixmap

all the time while scrolling.

ah, and XCopyArea of course ;)

This is weird... 

If I open a second tab in Chromium, the scrolling is OKAY. 

I don't even have to enter an URL in the second tab, just click on + for a new tab.

If I close the second tab, scrolling is slow again.

What could this be?

(In reply to comment #12)
> This is weird... 
> 
> If I open a second tab in Chromium, the scrolling is OKAY. 
> 
> I don't even have to enter an URL in the second tab, just click on + for a new
> tab.
> 
> If I close the second tab, scrolling is slow again.
> 
> What could this be?

hmm can't reproduce this behavior anymore (I closed chromium and started it again)

(In reply to comment #13)

> hmm can't reproduce this behavior anymore (I closed chromium and started it
> again)

Sorry for all the comments, but I found out why I had this fast scrolling. It was because I was testing WebGL. 

To reproduce fast scrolling:

1. open chromium, go to http://dev.chromium.org/developers/demos-gpu-acceleration-and-webgl

2. scroll, the page scrolls slow

3. click on the link to the aquarium demo (not the picture, that will open a new tab)

4. wait until everything is loaded and the fish are swimming

5. press the back button

5. scroll, the page scrolls fast

The problem is still there with this radeon r350 card and ubuntu 11.04 using xorg-edgers ppa. Slow scrolling in chromium and slow 2D performance in other apps.

3D performance is quite nice.

Gerwin, Ubuntu Maverick reached EOL on April 10, 2012. For more on this, please see https://wiki.ubuntu.com/Releases .

If this is reproducible in a supported release, it will help immensely if you filed a new report with Ubuntu by ensuring you have the package xdiagnose installed, and that you click the Yes button for attaching additional debugging information running the following from a terminal:
ubuntu-bug xorg

Also, please feel free to subscribe me to it.

For more on why this is helpful, please see https://wiki.ubuntu.com/ReportingBugs.