Tinker Caching & CDNs

by Kondasamy Jayaraman · drawn with Colorfigures by April Zhu

13:00: Larkspur’s shelves after the sale, with chapters 4 and 5’s fixes.9 from shelves · 6 to the depot · 6 trips

Chapter 6 of 7

The same trick everywhere

Larkspur’s shelves keep prices right and the depot calm. The team’s AI assistant runs on a model server. Does it keep copies too?

This chapter: Where else does the keep-a-copy trick show up?

About this chapter

You will learn

  • A prompt cache keeps work on a prompt’s opening
  • A KV cache keeps a reply’s work for that reply
  • The questions every cache answers

Words you’ll meet

Prompt cache
A provider’s store of work already done reading a prompt’s opening, reused by matching calls.
KV cache
The keys and values a model keeps for tokens it already read, so each new token computes only its own.

Step 1 of 3

Model providers keep copies too. A keeps the work done reading a prompt’s opening.

Predict what breaks a hit.

Your assistant’s next call changes one word in the first line of its prompt. What does the prompt cache do?