Equation 13 · Part 2 · AI Memory Systems and the Bandwidth Wall in 2035: Scenarios, Signals, and Falsifiable Predictions
Symbol L
What this part means
the number of layers.
Its job in the formula
L is an input to the expression that computes the quantity on the left.
Full expression→Symbol L→Article meaning
Where the article explains it
For a model with L layers, key-value heads, head dimension , sequence length S , batch size B , and p bytes stored per element, the cache occupies approximately .
The passage around this formula
Fact. The memory a transformer must hold for one in-flight generation — its key-value cache — grows linearly in exactly the variables that make serving expensive: sequence length and batch size. For a model with L layers, key-value heads, head dimension , sequence length S , batch size B , and p bytes stored per element, the cache occupies approximately . bytes, the leading factor of two accounting for keys and values together. That equation is worth writing out…
Learn the underlying idea
A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.
Open the illustrated variables: a letter stands for a value guide →
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Sources cited in the article section
- [15] DeepSeek-V2: A Strong, Economical, and Efficient Mixture-of-Experts Language Model ↗
- [14] Efficient Streaming Language Models with Attention Sinks ↗
- [16] H2O: Heavy-Hitter Oracle for Efficient Generative Inference of Large Language Models ↗
These citations provide research context; check each source for the exact claim it supports.