Problems / LLM serving, easy

Not enough concurrent streams

Each answer streams for about 4 seconds, and the deployment allows 100 concurrent streams. Traffic is 40 requests a second.

Free to open. Runs in your browser, no sign-up.

Your goals

Success ≥ 99%, time to first token p99 ≤ 2.5 s.

The traffic

40 requests a second for 30 seconds: 100% request (reads).

The system

What each component does in this design, and what calls it. The simulator mimics each one from these settings.

ComponentIts job hereSettings
Load balancerLoad balancerTraffic enters here.Calls AI app.Layer 4 balancers route by IP and port; layer 7 balancers read HTTP and can route by path or header.–
AI appApp serviceLoad balancer forwards to it.Calls Model.Little's law: throughput ≈ concurrency ÷ latency. 200 slots at 50 ms serve about 4,000 req/s.3 replicas × 500 slots · timeout 30 s
ModelLLM endpointAI app calls it.Latency has two parts: time to the first token, then a steady stream of tokens per second.100 streams

Hints

Try it first. Open one hint at a time if you get stuck.

Hint 1

Little’s law: streams in use = rate × stream time.

Hint 2

40 × 4 s = 160 streams.

One way to solve it

Raise the concurrent streams (or provisioned throughput) above 160 with headroom.

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