функции по сервис басу дергаются, а там в очереди по 1000+ сообщений висит
кстати про сервис бас вот
For Service Bus triggers, use Manage rights on resources for the most efficient scaling. With Listen rights, scaling isn't as accurate because the queue length can't be used to inform scaling decisions. To learn more about setting rights in Service Bus access policies, see Shared Access Authorization Policy.