a11y in Feisty testing by default
Henrik Nilsen Omma
henrik at ubuntu.com
Mon Nov 27 17:12:09 GMT 2006
Upstream Gnome has been discussing switching on the AT-SPI accessibility
framework by default in test builds of Gnome. The possibility of Ubuntu
doing the same was raised at UDS.
Obviously a distro is a different beast than an unstable version of a
desktop environment in that we may have a large number of users
participating throughout the testing cycle (upgrading from Edgy to
Feisty is easier than compiling Gnome from CVS). So we need to have a
separate discussion about this in Ubuntu.
I raised the question at last week's distro meeting. Colin had two main
concerns that I will return to here:
(a) if it's *too* broken it could seriously impede development
AT-SPI is not badly broken in that it causes major problems for the
system. If it was that bad we should reconsider shipping it in main.
However there are some known issues:
* There have been some very noisy but fairly harmless bugs (#62446)
* Running AT-SPI can cause crashes in other applications like
OpenOffice (bug #35313)
* With AT-SPI switched on the whole desktop is noticeably slower than
Of course these are precisely some of the things that we are trying to
improved with this expanded focus on testing. The little bits of code
cruft that cause all this should be easier to spot and fix with many
If an individual tester or developers finds the issues above to be too
annoying for daily use then the features can easily be switched off. A
personal setting will override the default. If it is felt that even that
is too intrusive then we can always roll the patch out again after a
week or two.
(b) how do we arrange to turn it off again for people who install
milestone releases of feisty and then upgrade?
If I have understood the design of the proposed patch correctly then
this is taken care of. See: http://bugzilla.gnome.org/show_bug.cgi?id=362457
A gconf schema change is made which turns AT-SPI on by default unless
the user has explicitly chosen otherwise AND is only triggered on odd
version numbers of Gnome. So installing Feisty pre-beta with Gnome 2.17
would leave AT-SPI on (unless switched off by the user) but upgrading to
Gnome 2.18 would set the default value to off.
[the one hitch there is that someone who needs these features and
installs Feisty without altering these settings will find AT-SPI being
turned off towards the end of the testing period -- However, I expect
the small group who falls into this category -- users of AT who use
unstable software -- will be fairly well read up on the issue and will
know how to deal with it].
Those proposing this change in upstream Gnome are hoping that it will
eventually lead to AT-SPI being permanently switched on in all
Gnome-based distributions. Personally I think we are still quite far
from that change. Much more performance and stability work needs to be
done and even then it is an open question whether we would ask our
general users to let their RAM and CPU cycles be used by features they
don't need. I'd personally like to see a dynamically loadable AT-SPI.
But that's for the future ... For now we should decide on the simple
question of general testing of AT-SPI in Feisty unstable. I think it is
reasonable to ask our testers and developers to try AT-SPI by default.
This group likely has more beefy hardware and a higher tolerance for
bugs than we can expect from our users.
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