This is a draft of the `tractor` way to implement the example from the
"processs pool" in the stdlib's `concurrent.futures` docs:
https://docs.python.org/3/library/concurrent.futures.html#processpoolexecutor-example
Our runtime is of course slower to startup but once up we of course get
the same performance, this confirms that we need to focus some effort
not on warm up and teardown times. The mp forkserver method definitely
improves startup delay; rolling our own will likely be a good hot spot
to play with.
What's really nice is our implementation is done in approx 10th the code ;)
Also, do we want offer and interface that yields results as they arrive?
Relates to #175
Using `None` as the default key for a `@msg.pub` can cause conflicts if
there is more then one "taskless" (no tasks={,} passed) pub offered on
an actor... So instead use the first trio "task name" (usually just the
function name) instead thus avoiding this very hard to debug and
understand problem.
Probably should throw in a test but I'm super lazy today.
This begins the move to dropping support for `tractor.run()` which we
don't really need since the runtime is started (as it always has been)
from a new sub-task / nursery. Instead this introduces starting the
actor tree through a `open_root_actor()` async context manager which
we'll likely implicitly call (from the root) on the first use of an
actor nursery.
Drop `_actor._start_actor()` and factor its contents into this new api.
Make `run()` and `run_daemon()` use `open_root_actor()` until we decide
to remove them.
Relates to #168 and #177
It turns out in order to maintain our sneaky little "call an `Actor`
method in this remote process" we still need the ability to invoke
functions from a namespace. We're currently using a "self" namespace as
a way to do this for internal inter-process method calling. Either way,
I see no reason not to keep a public method for this invoke style (we
just won't market it) since it is still how the machinery works
underneath.
Tyler Goodlet
goodboy