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by imtringued 423 days ago
>Even with that, there are obvious limitations described by Amdahl's law, which states there is a logarithmic maximum potential improvement by increasing hardware provisions.

I don't know why so many people are obsessed with Amdahl's law as some universal argument. The quoted section is not only 100% incorrect, it sweeps the blatantly obvious energy problem under the rug.

Imagine going to a local forest and pointing at a crow and shouting "penguin!", while there are squirrels running around.

What Amdahl's law says is that given a fixed problem size and infinite processors, the parallel section will cease to be a bottleneck. This is irrelevant for AI, because people throw more hardware at bigger problems. It's also irrelevant for a whole bunch of other problems. Self driving cars aren't all connected to a supercomputer. They have local processors that don't even communicate with each other.

>The latest innovations go far beyond logarithmic gains: there is now GPT-based software which replaces much of the work of CAD Designers, Illustrators, Video Editors, Electrical Engineers, Software Engineers, Financial Analysts, and Radiologists, to name a few.

>And yet these perinatal automatons are totally eviscerating all knowledge based work as the relaxation of the original hysterics arrives.

These two sentences contradict each other. You can't eviscerate something and only mostly "replace" it.

This is a very disappointing blog post that focuses on wankery over substance.

1 comments

We would see neither squirrels nor crows since these criticisms miss the forest for the trees. But we can address them.

> This is irrelevant for AI, because people throw more hardware at bigger problems

GAI is a fixed problem which is Solomonoff Induction. Further Amdahl's law is a limitation on neither software nor a super computer.

Both inference and training rely on parallelization, LLM inference has multiple serialization points per layer. Vegh et al 2019 quantifies how Amdahl's law limits success in neural networks[1]. He further states:

"A general misconception (introduced by successors of Amdahl) is to assume that Amdahl’s law is valid for software only". It would apply to a neural network as it does equally to the problem of self-driving cars.

> These two sentences contradict each other

There is no contradiction only a misunderstanding of what "eviscerates" means and even with that incorrect definition resulting in your threshold test, it still remains applicable.

1. https://pmc.ncbi.nlm.nih.gov/articles/PMC6458202/

Further reading on Amdahl's law w.r.t LLM:

2. https://medium.com/@TitanML/harmonizing-multi-gpus-efficient...

3. https://pages.cs.wisc.edu/~sinclair/papers/spati-iiswc23-tot...

I am new to Amdahl's law, but wouldn't a rearchitecture make it less relevant. For example if instead of growing an LLM that has more to do in parallel, seperate it into agents (maybe a bit like areas of the brain?). Is Amdahls law just a limit for the classic LLM architecture?
I don't think it can ultimately be escaped but the cited Vegh et al exactly proposes that, the bioinspiration, as a means to surpass those limitations.

However, in this article I contend that those limitations have posed little adversity in the field given the success of the latest models. As a result, it may be a bit premature to be concerned about it.