Retries and backoff

Retry counters

Each failure increments retries. If retries reaches max_retries, the task is discarded during refresh().

on_failure behavior

queue.on_failure(task, error_message="timeout")

on_failure(): - clears assignment fields - increments retries - optionally schedules a retry based on backoff settings

Exponential backoff

Backoff uses:

delay = retry_backoff_base * (2 ** max(retries - 1, 0))

retry_backoff_max caps the delay.

Manual retry

Use on_retry(task, delay_seconds=...) to release a leased task back to new with an optional delay.