Right now, the host setup is done globally upfront. This means that an invocation of py.test can send tests only to a single set of hosts.
It would be nice to be able to customise this in the
conftest.py files so that I can indicate that all tests in (say) "test_foo" directory should be run on host X. The person who invokes the tests wouldn't need to care and can directly just run tests. The config options would take care of distributing the tests to the right machines.