EXA and MigrationHeuristic

[Bryce Harrington]

On Wed, May 28, 2008 at 08:46:30PM +0200, Juliusz Chroboczek wrote:
> Isn't the default value of MigrationHeuristic incorrect ?  Should we
> switch to greedy as default ?  (Julien tells me that he believes that
> Ubuntu have already made the switch.)

For Ubuntu, we switched to greedy as the default for -intel only, after
consulting with Jesse about it.  I was told the change I put in was fine
at the distro level but not for xorg in general.

That said, we saw extremely positive results from users in testing with
the greeedy migration heuristic for Hardy, and only a scattering of (not
solidly confirmed) reports of problems.

There were also many anecdotal reports that greedy on -ati improved
things when running EXA, but given the QA investment it took during
Hardy LTS development to get a stable EXA-enabled -intel, we decided to
wait until Intrepid to focus on EXA for -ati.  I'm glad to see Alex's
reports about all the progress that's been made in the meantime and hope
to spend some time in coming months kicking tires on it.

Bryce