getting the following error / when running backtests.

‘500 Server Error: INTERNAL SERVER ERROR for url: http://houston/zipline/backtests/a13v_sieg?data_frequency=daily&capital_base=100000.0&bundle=usstock-1d-bundle&start_date=2015-01-01&end_date=2020-11-26&progress=M’, {‘status’: ‘error’, ‘msg’: “can’t start new thread”})

Whenever a 50x error is returned, always the first thing you should do is to look at the detailed logs to see the full traceback.

log is below:

quantrocket_zipline_1|Traceback (most recent call last):
quantrocket_zipline_1| File “sym://qrocket_app_py”, line 738, in post
quantrocket_zipline_1| File “sym://qrocket_qrzipline_backtest_py”, line 167, in backtest_algo
quantrocket_zipline_1| File “/opt/conda/lib/python3.6/site-packages/zipline/algorithm.py”, line 669, in run
quantrocket_zipline_1| for perf in self.get_generator():
quantrocket_zipline_1| File “/opt/conda/lib/python3.6/site-packages/zipline/gens/tradesimulation.py”, line 223, in transform
quantrocket_zipline_1| algo.before_trading_start(self.current_data)
quantrocket_zipline_1| File “/opt/conda/lib/python3.6/site-packages/zipline/algorithm.py”, line 473, in before_trading_start
quantrocket_zipline_1| self._before_trading_start(self, data)
quantrocket_zipline_1| File “a13v_spyx3”, line 26, in before_trading_start
quantrocket_zipline_1| File “./codeload/zipline/a13vta.py”, line 28, in API_INIT
quantrocket_zipline_1| handler = FlightlogHandler()
quantrocket_zipline_1| File “/opt/conda/lib/python3.6/site-packages/quantrocket/flightlog.py”, line 119, in FlightlogHandler
quantrocket_zipline_1| listener.start()
quantrocket_zipline_1| File “/opt/conda/lib/python3.6/logging/handlers.py”, line 1412, in start
quantrocket_zipline_1| t.start()
quantrocket_zipline_1| File “/opt/conda/lib/python3.6/threading.py”, line 846, in start
quantrocket_zipline_1| _start_new_thread(self._bootstrap, ())
quantrocket_zipline_1|RuntimeError: can’t start new thread

and now houston is down / and cannot restart

This site can’t be reached

quantrocket-x.frantescu.com refused to connect.



Debugging of Zipline algos goes beyond the scope of the support forum. Please reach out about paid support if you want to dig into that.

The same applies to general network issues with your cloud deployment. That’s not a QuantRocket-specific issue, but again I would be happy to help in any way I can under the framework of paid support.