Radeon Driver: Change from XAA to EXA

Registered by Bryce Harrington on 2008-11-03

The open source -radeon / -ati driver still uses XAA by default in Intrepid. For Jaunty, evaluate changing to the new EXA.

While as a new technology EXA may not be 100% stable yet, neither is XAA without problems. And lately we're noticing a pattern where -ati users with problems in XAA see them disappear when switching to EXA. However, much of this data is anecdotal. Even so, upstream is also encouraging switching to EXA by default, and may be doing this themselves soonish.

For Jaunty, we should change to EXA by default for -ati / -radeon for community testing.
Extra efforts should be put into getting EXA issues forwarded upstream.
Existing XAA bugs marked "Needs EXA" should not be closed prior to Alpha-5.

At Alpha-5 we will revert back to XAA unless the following criteria are met:
a) No critical bugs specific to EXA are open against xserver-xorg-video-ati
b) All High-importance EXA -ati issues are either forwarded upstream or have a patch in the works on our end
c) There are no more than a dozen high or medium priority EXA-specific -ati issues open

Blueprint information

Status:
Complete
Approver:
Martin Pitt
Priority:
Medium
Drafter:
Bryce Harrington
Direction:
Needs approval
Assignee:
Bryce Harrington
Definition:
Approved
Series goal:
Accepted for jaunty
Implementation:
Implemented
Milestone target:
None
Started by
Bryce Harrington on 2008-12-18
Completed by
Bryce Harrington on 2009-02-17

Related branches

Sprints

Whiteboard

This probably won't require much UDS discussion. I've proposed for UDS but maybe it could be covered in a single general purpose X session.

2008-11-18 bryce: Discussion with upstream and testers indicates switching -ati to EXA for jaunty makes good sense.

2008-12-18 bryce: Fleshed out blueprint spec. Implementation is fairly simple and will be done once alpha-2 is out the door. For deployment we'll focus on bug fixing. The evaluation whether to keep EXA or revert to XAA will be made around Alpha-5; that should give sufficient time for thorough testing.

2008-12-19 pitti: wouldn't it be a better/additional metrics to take the number of regression bug reports and weight it against the number of bugs which got fixed by switching to EXA?

2008-12-19 bryce: well that could get tricky to keep track of, but makes sense. I've updated the blueprint.

2008-12-19 bryce: the switch to EXA has just been rolled out for -ati.

2008-12-20 pitti: Thanks; I don't think we should look at precise numbers, but if you have the feeling that the number of regressions is on the same magnitude than the number of bug fixes, we should reconsider this. If it's much smaller, we should keep it. Approved.

2008-12-19 fabio: It would be nice to update the -ati version in jaunty to, at least, 6.9.0.91 (already in debian experimental), which has a number of fixes related to EXA. Currently there is the old git version 6.9.0+git20081003.f9826a56-0ubuntu6.

2009-01-05 bryce: Done, we've sync'd the beta from debian experimental.

2009-02-17 bryce: We're not quite to alpha-5, but it's close enough. We were able to close about half a dozen XAA bugs when switching to EXA, and there hasn't been notable regressions. Bug 315889 sounded like a regression, but ended up just being because fglrx was still installed and was interfering with -ati, so had nothing to do with EXA. If there does happen to be a regression or two with moving from XAA to EXA, I'm pretty confident it can be addressed just as an ordinary bug. Closing this spec as done.

(?)

Work Items

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