Five hundred workers call a downstream API every minute
A medium Pipeline Design mock interview question on DataDriven. Practice with AI-powered feedback, real code execution, and a hire/no-hire decision.
- Domain
- Pipeline Design
- Difficulty
- medium
Interview Prompt
Five hundred workers call a downstream API every minute. A brief latency spike caused all 500 to time out at the same instant. Every worker retries on a fixed one-second sleep, so 500 retries arrive at the downstream simultaneously one second later. The retries themselves become the load. The section names this a thundering herd. Find the herd by replacing the fixed-delay retry with one whose name states both halves of the section's fix: a backoff schedule (wait longer between successive retries) and a jitter strategy (random offset that desynchronizes the wave).
How This Interview Works
- Read the vague prompt (just like a real interview)
- Ask clarifying questions to the AI interviewer
- Write your pipeline design solution with real code execution
- Get instant feedback and a hire/no-hire decision