Spyder hangs on calling random.uniform()

Question

My program frequently access random numbers. I initiate my random number generator via:

import random
random.seed(1)

I'm calling random.uniform() a lot in code for an evoluationary model (biology) and it repeatidly hangs (doing nothing for 20 minutes and then I stop it) after a while. While it hangs Python is using my CPU with 20%-30% (I have four cores). At the same time it's using 10GB Ram (I am having a lot of data).

Can I do something to make the default random library not hang or is there another random libary I can use?

I'm running Spyder 4.2.5 with Python 3.8 on Windows 10. (The problem already existed with an earlier version of Spyder and I installed Spyder 4.2.5 from skretch)

are you using random from a thread? does it behave this way if you disable the pagefile? heavy-handed, but does using a more science-oriented operating system help? — ti7, Jun 12 '21 at 14:34

ti7 · Answer 1 · 2021-06-11T21:18:11.883

Just speculating, but the default random module definitely shouldn't do that, so I suspect either

there's something wrong with your Python install itself
your system doesn't have enough entropy (or you are exhausting the pool by making a massive number of sequential calls to it, rather than simply using the base value) and is relying on /dev/random (which blocks until data is available) .. see related
- differences between random and urandom
- https://www.python.org/dev/peps/pep-0524/

Try calling os.random with and without the blocking flag

import os
os.getrandom(1024, flags=os.GRND_NONBLOCK)  # raise for low entropy

Spyder hangs on calling random.uniform()

1 Answers1