Python hung (likely because of too many psycopg2 connections) during attempted impmentation of https://github.com/deepmind/scalable_agent

[halessi]

The graph assembles just fine, after finalization and onto training, one of the threads (assuming main?) gets hung. This is the traceback:

-------------------- Thread 4590249408 -------------------- File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/threading.py", line 884, in _bootstrap self._bootstrap_inner() File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/threading.py", line 916, in _bootstrap_inner self.run() File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/threading.py", line 864, in run self._target(*self._args, **self._kwargs) File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/site-packages/tensorflow/python/training/queue_runner_impl.py", line 257, in _run enqueue_callable() File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 1257, in _single_operation_run self._call_tf_sessionrun(None, {}, [], target_list, None) File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 1407, in _call_tf_sessionrun run_metadata)

also get this traceback for the same thread (getting hung here as well?):

File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/threading.py", line 884, in _bootstrap self._bootstrap_inner() File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/threading.py", line 916, in _bootstrap_inner self.run() File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/threading.py", line 864, in run self._target(*self._args, **self._kwargs) File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/site-packages/tensorflow/python/training/queue_runner_impl.py", line 293, in _close_on_stop coord.wait_for_stop() File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/site-packages/tensorflow/python/training/coordinator.py", line 311, in wait_for_stop return self._stop_event.wait(timeout) File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/threading.py", line 551, in wait signaled = self._cond.wait(timeout) File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/threading.py", line 295, in wait waiter.acquire()

Thread traceback acquired using https://gist.github.com/niccokunzmann/6038331. I'm assuming this is because each instance of the btc_env creates a new psycopg2 connection to the history database hosted by postgresql, however I do not know how to fix it.

Although I know this is an outside project, any insight would be greatly appreciated. If the deepMind IMPALA implementation demonstrates decent results, I would be happy to share the implementation here if I can get it working.

[halessi]

Apologies, the same thread also has this traceback as well (i.e. is getting stuck for more than 10 seconds):

-------------------- Thread 4590249408 -------------------- File "run.py", line 656, in tf.app.run() File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/site-packages/tensorflow/python/platform/app.py", line 125, in run _sys.exit(main(argv)) File "run.py", line 650, in main train(action_set, level_names) File "run.py", line 571, in train lambda step_context: step_context.session.run(stage_op)) File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/site-packages/tensorflow/python/training/monitored_session.py", line 732, in run_step_fn return self._sess.run_step_fn(step_fn, self._tf_sess(), run_with_hooks=None) File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/site-packages/tensorflow/python/training/monitored_session.py", line 1176, in run_step_fn return self._sess.run_step_fn(step_fn, raw_session, run_with_hooks) File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/site-packages/tensorflow/python/training/monitored_session.py", line 1083, in run_step_fn return step_fn(_MonitoredSession.StepContext(raw_session, run_with_hooks)) File "run.py", line 571, in lambda step_context: step_context.session.run(stage_op)) File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 929, in run run_metadata_ptr) File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 1152, in _run feed_dict_tensor, options, run_metadata) File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 1328, in _do_run run_metadata) File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 1334, in _do_call return fn(*args) File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 1319, in _run_fn options, feed_dict, fetch_list, target_list, run_metadata) File "/Users/hughalessi/miniconda3/envs/rl/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 1407, in _call_tf_sessionrun run_metadata)