grace period for deleting VMs

circle/vm/tasks/local_periodic_tasks.py

@@ -42,8 +42,11 @@ def garbage_collector(timeout=15):
     :type timeout: int
     """
     now = timezone.now()
+    grace_period = timezone.timedelta(hours=1)
+    work_package = 20
     for i in Instance.objects.filter(destroyed_at=None).all():
-        if i.time_of_delete and now > i.time_of_delete:
+        if i.time_of_delete and now > i.time_of_delete + grace_period and work_package > 0:
+            work_package -= 1
             i.destroy.async(system=True)
             logger.info("Expired instance %d destroyed.", i.pk)
             try:
@@ -57,7 +60,8 @@ def garbage_collector(timeout=15):
                 logger.debug('Could not notify owner of instance %d .%s',
                              i.pk, unicode(e))
         elif (i.time_of_suspend and now > i.time_of_suspend and
-              i.state == 'RUNNING'):
+              i.state == 'RUNNING') and work_package > 0:
+            work_package -= 1
             logger.info("Expired instance %d suspended." % i.pk)
             try:
             	i.sleep.async(system=True)