Buildbot improvements

[DJ Delorie]

Adhemerval Zanella <adhemerval.zanella@linaro.org> writes:
> I take this builbot setup is used along with Fedora to stress both systems,
> but maybe it would better to use a more stable baseline to make it easier
> to reproduce.  Either Fedora current or a way to download the required
> packages/tools.

I use the published registry.fedoraproject.org/fedora base container.
We chose to use the latest container for security reasons, to make sure
we had all the current security errata etc.  It probably won't change
often enough to be an issue, but it means that I can't guarantee an
exact reproduction of a given trybot container.

Even if the containers were published, the trybot's container includes a
full copy of the glibc git tree at that moment, and we're hoping that
there will eventually be many trybots - not just mine - so consider the
cost of moving all that data around vs just running your own trybot ;-)

Note that I'm not defending my choice here, just explaining it.  I'm
open to new ideas and tweaks.