Added an option to skip adding /var/lib/juju to juju-crashdump.

[petevg]

Useful for automated testing frameworks, which don't necessarily want to
create a huge tarball each time.

@johnsca, @kwmonroe Thinking about this, I think that it makes sense to include /var/lib/juju in juju-crashdump when it is run manually. You are trying to diagnose a problem, and saving off the state of the /var/lib/juju dir is useful for that diagnosis.

I don't think that it's so useful that it needs to be included in the automated tests, though. If you agree with this approach, the next step is to pass "-s" in matrix (and bundletester).

... and the next step after that might be to only crashdump when we have a test failure.

[ktsakalozos]

LGTM +1 . Not merging yet since you are asking for the feedback of @johnsca and @kwmonroe

[johnsca]

I'm fine with this approach.

[lutostag]

Which files are large in there, we have a 5MB limit for files to include in the made bundle. Is that not being followed?

[kwmonroe]

@lutostag it's not a single file that's large -- it's the /var/lib/juju/agents/unit-foo/charm/.venv that hurts (that dir can easily get to 10s of MBs).

[kwmonroe]

+1, lgtm

[johnsca]

I wasn't aware of the 5MB limit. Maybe it makes more sense to simply blacklist the .venv directory?

[lutostag]

Should probably only be collected on actual test failures. But, I do like the idea of a --small flag, that we can have a better rule for what not to include in the future. This is a good start.
+1

[johnsca]

Per discussion on IRC, we're all +1 on this PR with the understanding that the heuristic for "small" is improved in the future.