Run tests for all arches in lxd

[Iain Lane]

lxd tests are faster and can be more dense. Doing this would improve throughput.

Caveat is that lxd doesn't support the 'isolation-machine' restriction, so we need to fall back to qemu/ssh in those cases. We can't actually easily know when to do this ATM, since the list of restrictions is only kept within the source package.

[Iain Lane (laney)]

Current thought is to have dpkg expose this in the .dsc, so it ends up in Sources, and then we can look at the field and dispatch as required.

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=847926

[Steve Langasek (vorlon)]

Iain, are you still thinking this would be an improvement? There are obviously plenty of packages requiring isolation-machine for which we'd still need to run VMs in order to have test coverage. Would this just be added complexity at this point now that we're ok on capacity across architectures?

[Iain Lane (laney)]

lxd tests are much faster to push through, so this would still be interesting. But my initial dpkg fix got committed, released and then reverted when Ian Jackson complained. My several followup queries were ignored, and so we have no way to get this information easily. I am not interested in maintaining an out of band list of Testsuite-Restrictions, so realistically I'm probably not going to work on it.