Qlib Frequently Asked Questions¶
1. RuntimeError: An attempt has been made to start a new process before the current process has finished its bootstrapping phase…¶
RuntimeError: An attempt has been made to start a new process before the current process has finished its bootstrapping phase. This probably means that you are not using fork to start your child processes and you have forgotten to use the proper idiom in the main module: if __name__ == '__main__': freeze_support() ... The "freeze_support()" line can be omitted if the program is not going to be frozen to produce an executable.
This is caused by the limitation of multiprocessing under windows OS. Please refer to here for more info.
Solution: To select a start method you use the
D.features in the if __name__ == ‘__main__’ clause of the main module. For example:
import qlib from qlib.data import D if __name__ == "__main__": qlib.init() instruments = ["SH600000"] fields = ["$close", "$change"] df = D.features(instruments, fields, start_time='2010-01-01', end_time='2012-12-31') print(df.head())
2. qlib.data.cache.QlibCacheException: It sees the key(…) of the redis lock has existed in your redis db now.¶
It sees the key of the redis lock has existed in your redis db now. You can use the following command to clear your redis keys and rerun your commands
$ redis-cli > select 1 > flushdb
If the issue is not resolved, use
keys * to find if multiple keys exist. If so, try using
flushall to clear all the keys.
qlib.config.redis_task_db defaults is
1, users can use
Also, feel free to post a new issue in our GitHub repository. We always check each issue carefully and try our best to solve them.