Hello, Load Balancer – junior-level system design challenge

One API server is drowning under 1,500 RPS. Get error rate to zero without touching the traffic.

Requirements

• Traffic: 1,500 req/s
• p99 latency: ≤ 500 ms
• Errors: ≤ 0.5%

Goal

Hold p99 latency under 500ms, error rate under 0.5% through every stage of the test plan, then compare your design with a reference design.

The test plan

1. Lunch rush: 1,500 requests per second.

Hint

A single m7g.large handles about 1,000 RPS. Put a Load Balancer in front and add a second server behind it.

Solve it on the live simulator, free and in your browser.

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