Implement Connection.__del__, which is almost certainly going to trigger
more bugs down the line, because the state of the Connection instance is
not guranteed during __del__. Meanwhile, it is temporarily needed for
deployed-today Ansibles that have a buggy synchronize action that does
not call Connection.close().
A better approach to this would be to virtualize the guts of Connection,
and move its management to one central place where we can guarantee
resource destruction happens reliably, but that may entail another
Ansible monkey-patch to give us such a reliable hook.
The strategy is reconstructed for every playbook that is included or
specified on the command line, therefore we can't store the global
Router there without losing all our SSH connections across playbooks.
Turns out Ansible can't be trusted to actually check the result
dictionary everywhere it expects one, so put the real exception text
into -vvv output too.
Ansible's PluginLoader makes up bullshit when it imports a module
(mostly because it has to make up something), therefore we ended up with
duplicate copies of ansible_mitogen loaded: one under
ansible.plugins.*.mitogen, and one under the canonical namespace.
Which broke isinstance().
It's used at least by the copy module, even though the result is still
mostly a no-op. _remote_chmod() doesn't accept octal mode, it accepts
symbolic mode. So implement a symbolic parser in helpers.py.
Still needs a ton of work to emulate argument handling, shell selection,
and output emulation in every case. Unsurprisingly, Ansible documents
none of this.
On Python 2.x, operations on pthread objects with a timeout set actually
cause internal polling. When polling fails to yield a positive result,
it quickly backs off to a 50ms loop, which results in a huge amount of
latency throughout.
Instead, give up using Queue.Queue.get(timeout=...) and replace it with
the UNIX self-pipe trick. Knocks another 45% off my.yml in the Ansible
examples directory against a local VM.
This has the potential to burn a *lot* of file descriptors, but hell,
it's not the 1940s any more, RAM is all but infinite. I can live with
that.
This gets things down to around 75ms per playbook step, still hunting
for additional sources of latency.
David Wilson