KV cache — The memory a model keeps about text it has already read, so generating each new token doesn't require reprocessing the whole conversation.
distillation — Training a small, cheap model to imitate a big one's outputs, keeping much of the capability at a fraction of the cost.
context window — The maximum amount of text a model can consider at once — its working memory for the current conversation or task.
Why it matters
Two models with identical cache sizes can differ sharply in memory utilization; ESS measures the gap and predicts which models distill badly and which handle recall-heavy context windowThe maximum amount of text a model can consider at once — its working memory for the current conversation or task.Full definition → well.