Upper limit in Python time.sleep()?

Actual answer, at least for my machine: 4294967.2950000003911900999... seconds.

sleep(4294967.2950000003911901)

OverflowError: sleep length is too large

Others have explained why you might sleep for less than you asked for, but didn't show you how to deal with this. If you need to make sure you sleep for at least n seconds you can use code like:

from time import time, sleep
def trusty_sleep(n):
    start = time()
    while (time() - start < n):
        sleep(n - (time() - start))

This may sleep more than n but it will never return before sleeping at least n seconds.

I suppose the longer the time the more probable situation described in the docs:

The actual suspension time may be less than that requested because any caught signal will terminate the sleep() following execution of that signal’s catching routine. Also, the suspension time may be longer than requested by an arbitrary amount because of the scheduling of other activity in the system.