10 · Keep useful work on the GPU

Deep systems understanding · Study map 46 of 85

Continuous batching: refill seats every iteration

Suggested preparation: PagedAttention: grow conversations in blocks

Picture it

Picture a Ferris wheel where the operator waits for every single rider to finish a 10-minute ride before letting anyone new get on. Continuous batching changes the rules, allowing new riders to hop into empty carts the moment someone steps off, keeping the wheel constantly packed. This beautifully orchestrates the GPU's momentum, ensuring no seat is ever empty, though it demands a brilliant juggler to keep track of everyone's tickets.

What to understand

  • Iteration-level scheduling, admission, and token budgets
  • Batch size versus latency, memory, fairness, and throughput

Follow the references

  1. 1 · Book chapter

    How To Scale Your Model · Transformer inference ↗

    Read continuous batching and compare it with a fixed request batch.

  2. 2 · Documentation

    vLLM · Optimization and tuning ↗

    Study the sequence and token-budget controls rather than copying default values.

Make it concrete

Sweep concurrency on a mixed-length workload. Find the point where throughput gains flatten while p95 latency or preemption rises.

You understand it when…

Why are 32 requests with 20-token outputs unlike 32 requests with 2,000-token outputs?

This is a study map. Follow the reference for the full explanation; use the question to test your mental model. Browse the reference shelf.