I have a dead-letter policy configured for my Google Pub/Sub subscription as:
...
dead_letter_policy {
dead_letter_topic = foobar
max_delivery_attempts = x
}
{
"minimumBackoff": y,
"maximumBackoff": z
}
...
Plugging in various values, i am not seeing the retries happen at times i would expect. E.g.
max_delivery_attempts: 5 minimumBackoff: 10 Seconds maximumBackoff: 300 Seconds
Seconds between retries: 15 17 20 29
max_delivery_attempts: 30 minimumBackoff: 5 Seconds maximumBackoff: 600 Seconds
Seconds between retries: 12 9 9 14 15 18 24 24 45 44 58 81 82 120 ..., and so on.
From this testing, it seems u need a high max attempts value to get actual exponential back-off? For my first data set, i would have expected the time between my last 2 attempts would have been closer to 300. From my second data set, it seems this would only be the case if the max attempts is set to the max value of 100. Is this assumption correct?
(also, this is a pull subscription)
Thanks