What is an active AI model parameter?

Definition

In sparsely activated models, only part of the total parameter set is used for a given token. The active-parameter count helps describe the computation performed per step, while the total-parameter count describes the larger capacity that must be stored.

A small active count does not guarantee low latency because weights must still be loaded and data must move through memory and interconnects. Hardware layout and routing overhead can be as important as arithmetic.

ELI5

An active AI model parameter is one of the learned values that actually takes part in calculating the answer for a particular input. Some models use nearly all their parameters each time, while sparse models choose only certain specialist sections for each piece of work.

For example, a model may contain ten groups of specialist parameters but route one token through only two groups. Those selected values are active for that step, which helps explain computing demand, although memory movement, context length, and software efficiency also affect speed.

How is an active-parameter count different from a total-parameter count?

The active count covers weights used for a particular step, while the total count includes every stored model weight.

Does a lower active-parameter count always make inference faster?

No. Memory bandwidth, routing, communication and software efficiency can limit speed even when fewer weights are computed.

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Definition card for active AI model parameter: What is an active AI model parameter?

An active AI model parameter is a model weight selected to participate in computation for a particular token or inference step.