1) I receive this : {"status":"ok","batch_size":100,"sent":100,"success":96,"failure":4}
The failure value change every time: what it depends on. How can I have info on this failure?

2) I've changed batch_size from 10 to 100. My table contains more then 500 devices and it's growing. Is suitable this value or can I set 500?

3) When devices are about 5000, is there a way to run the scheduler until the queue completes, avoiding having to run it with a cron? When the queue is empty the cron will work inadvertently

Thanks in advance.