Comment 259 for bug 252094

Bryce—

My apologies for adding to an already long bug, but I do have a comment regarding your last post. I'm hoping that you can help me decide where to start with new, more specific bug reports, but also I want to provide some perspective about why this is harder than it seems.

The behaviour reported with glxgears's low fps is not exclusive to glxgears; it just happens to be the best way I (and presumably many others) know of getting a reasonable framerate number that's consistent relative to other systems running the same hardware. Granted, it is not a good exhaustive test of video performance, but as a "do we have a problem here" benchmark, it seems to do a good job illustrating the dramatic difference between different software versions (especially since other 3D benchmarks seem to be basically unusable at this point, at least on my system).

This performance problem is not exclusive to glxgears reporting lower than expected framerates; it also occurs when playing a video with mplayer, or using a visualiser in amarok, or displaying pages in Firefox with lots of animation, or running a 2D or 3D DirectX application in wine, or.. well, basically anything to do with writing to the screen. Trying to run more than one application that updates the screen at regular intervals grinds things to a halt very very quickly. (For example, I can only watch videos in mplayer if Amarok has all of its windows closed. Even if Amarok's windows are in the background, or minimised, or if Amarok is paused and not doing anything, playback in mplayer will still be jerky until the windows are closed completely.)

It's challenging to split out the problem into different components in part because it is so pervasive throughout the system, which is why I think that we've ended up with this huge monolithic "performance is bad" bug. 2D performance is slow, 3D performance is slow... everything is just extremely, extremely slow, and anyone with an Intel video chipset is severely affected by this problem.

I would like to do whatever I can to form reasonable, reduced, and reproducible bug reports. I am just at a bit of a loss as to where to start because there's no specific place where I can go "this works OK, but this doesn't". Nothing works. It's all slow. Throw a stone and you'll hit something that isn't performing as it should. So, if you can tell me what you think would work well as a test report that can be sent upstream easily, let me know and I'll write it. I just personally feel a little overwhelmed with the amount of brokenness to try to start picking apart all the different issues and choosing the best one to report (and if I tried to report them all, I'd probably be here until next year).

Regards,