limit cronjob rate if multiple cronjobs end up in queue

pandora/app/models.py

@@ -42,6 +42,3 @@ class Settings(models.Model):
         else:
             value = default
         return value
-
-
-

pandora/app/utils.py

@@ -0,0 +1,17 @@
+# -*- coding: utf-8 -*-
+# vi:si:et:sw=4:sts=4:ts=4
+from __future__ import division, with_statement
+
+import time
+
+from .models import Settings
+
+
+def limit_rate(key, timeout):
+    key = 'limit.%s.last' % key
+    last_cronjob = Settings.get(key, 0)
+    current_time = time.time()
+    if (current_time - last_cronjob) > timeout:
+        Settings.set(key, current_time)
+        return True
+    return False

pandora/item/tasks.py

@@ -5,19 +5,22 @@ from datetime import timedelta, datetime
 import gzip
 import random
 
+from celery.task import task, periodic_task
 from django.conf import settings
 from django.db import connection, transaction
 from django.db.models import Q
 from ox.utils import ET
-from celery.task import task, periodic_task
 
-import models
+from app.utils import limit_rate
 from text.models import Text
 from taskqueue.models import Task
 
+import models
+
 
 @periodic_task(run_every=timedelta(days=1), queue='encoding')
 def cronjob(**kwargs):
+    if limit_rate('item.tasks.cronjob', 8 * 60 * 60):
         update_random_sort()
         update_random_clip_sort()
 

pandora/tv/tasks.py

@@ -4,10 +4,13 @@ from datetime import timedelta
 
 from celery.task import periodic_task
 
+from app.utils import limit_rate
+
 import models
 
 
 @periodic_task(run_every=timedelta(days=1), queue='encoding')
 def update_program(**kwargs):
+    if limit_rate('tv.tasks.update_program', 8 * 60 * 60):
         for c in models.Channel.objects.all():
             c.update_program()