Managing Long Running Tasks medium
What is a 'Zombie Task'?
- A A virus.
- B A deleted task.
- C A task that a worker started but never finished (due to crash), which holds up resources or prevents completion until the Visibility Timeout expires.
- D A task for Halloween.
Answer: C. A task that a worker started but never finished (due to crash), which holds up resources or prevents completion until the Visibility Timeout expires.
They appear 'alive' but are actually dead, waiting to be reaped.
One system design question a day, with spaced repetition so the ones you miss come back.
Get the appRelated questions
- What is the primary purpose of a Dead Letter Queue (DLQ)?
- The architectural pattern where one service creates tasks and another processes them is called:
- In a Priority Queue system (High vs Low), what is 'Starvation' and how do you fix it?
- How do you atomically update your local database AND publish a message to a queue without losing sync if the process crashes in between?
- What does 'Fire and Forget' mean?
- Why might you 'Throttle' (limit the speed of) your background workers?