Working with django-cron, should forever have near this CronJob. Shortly, this CronJob erased (drops/remove/delete) old log records from django-cron from DB.

gistfile1.txt

# coding=utf-8

from datetime import date, timedelta
import logging
from django_cron import CronJobBase, Schedule
from django_cron.models import CronJobLog

logger = logging.getLogger('captcha')

class DropLogs(CronJobBase):
    RUN_EVERY_MINS = 60*24*7 # week
    
    schedule = Schedule(run_every_mins=RUN_EVERY_MINS)
    code = 'drop_logs'
    
    def do(self):
        CronJobLog.objects.filter(start_time__lt=date.today()-timedelta(minutes=self.RUN_EVERY_MINS)).delete()
        logger.info('Logs dropped')