Comment 45 for bug 177492

Vincenzo, in the original discussion (comments 4, 6 from Timo), the plan all along had been to switch back to XAA after alpha3 for stability and performance. However, 965 is *really* broken with XAA so we planned to stay with EXA for that. It was even more broken with EXA, but the greedy patch you guys identified solved that. Thus the patches we uploaded.

The reports about EXA being fine and faster than XAA for <965 were rather anecdotal, so I guess they didn't capture our attention as well as the 965 issues. However, it's true there's a *lot* of these anecdotes especially now that I look. In any case, I had a hunch we might want to adjust the fix, so I did the change in two pieces - specifically so we could revert one or the other as needed.

Anyway, since we've been running EXA a while, and since upstream is encouraging dropping XAA anyway, I guess it does little harm for us to leave EXA on, so we'll go ahead and drop that patch 06 at this time.

I am also interested in seeing more detailed testing of use of the greedy flag for EXA on <965. It'd be fairly trivial to extend the greedy patch to cover all chipsets, but I don't know if doing so could cause regressions for a lot of folk.