cron_control.py

from psutil import virtual_memory
from functools import wraps

MIN_VM_SHARE = 0.10
MAX_CRON_PROCESSES = 5

def cron_control(func=None):
    
    @wraps(func)
    def wrapped(*args, **kwargs):
        vm = virtual_memory()
        if vm.free < MIN_VM_SHARE * vm.total:
            return None # virtual memory usage over limit
        elif len(__get_cron_processes()) > MAX_CRON_PROCESSES: # strict inequality
            return None # process count over limit
        else:
            return func(*args, **kwargs)

    return wrapped