Equation 12 · The Physical Economics of Inference: Bandwidth, Energy, and the Limits of a Datacenter
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Symbol e
the average energy per byte moved off-chip, energy per token is roughly e B/b — the weight traffic divided across the batch, plus each request’s own cache traffic.
Symbol B
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Symbol b
b is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
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The energy version of the same expression is more useful still. If e is the average energy per byte moved off-chip, energy per token is roughly e B/b — the weight traffic divided across the batch, plus each request’s own cache traffic. Batching therefore improves energy per token steeply at first and then asymptotically, converging on the irreducible per-request cache cost. That asymptote is the floor referred to throughout this article, and only cache-reduction techniques lower it.
For background, read the article’s source list.
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