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Re:Three chips in and Google Tensor is on life support by peterhull90 on Thursday November 23, 2023 @05:39AM (#38391378)
Can anyone just clarify for me what these AI / Machine learning chips are? As far as I can tell they are general purpose microprocessors with some added instructions which accelerate operations that are commonly used (matrix multiplication possibly?) but there's a lot I don't quite understand because some of the info is marketing and some of it it heavy technical stuff and my knowledge falls in between!
Re:Three chips in and Google Tensor is on life support by electricships on Thursday November 23, 2023 @05:58AM (#38391503)
here is my good deed for the day:

modern AI is just vector multipication. any AI chip is just 10,000s of very simple cores which can do vector float operations and little else. this also entails clever trade offs of shared cache and internal bandwidth.

(as a thought experiment, consider a naive million by million matrix multipication. this will take a single cpu about 1 year! how do we reduce this to 1s ?)

the end

Re:Three chips in and Google Tensor is on life support by automatic6131 on Thursday November 23, 2023 @06:22AM (#38391620)
>vector float operations and little else

I thought they were generally int8 or int16 vector multiply adds and occasionally float16 added in.

Re:Three chips in and Google Tensor is on life support by Symmetry on Thursday November 23, 2023 @07:03AM (#38391850)
Nowadays AI chips are specialized in not just vector multiplication but matrix multiplication. Just as moving from scalar math to vectors brings savings in control and routing logic, moving from vector to matrix does the same. Taking a result from a floating point unit and moving it to a big, multi-ported register file and then reading it out again to feed into another floating point unit is often a much bigger draw of power than the multiplication or addition itself and to the extent you can minimize that by feeding the results of one operation direction into the processing structures for the next you've got a big win.
Re:Three chips in and Google Tensor is on life support by exikyut on Thursday November 23, 2023 @06:39AM (#38391717)
As someone with a lot of interest in but no fluency with chip design, or the dividing and conquering of math within silicon, for that matter, how would you multiply a 1m² matrix?
Re:Three chips in and Google Tensor is on life support by financltravsty on Thursday November 23, 2023 @08:15AM (#38392407)
Parallelization.

Each "unit of work" in matrix multiplication is not dependent on any other unit of work. Stuff as many cores as you can into a chip, and then simply feed in all your vectors at the same time.

I.e. basically a beefed up GPU or an "AI" chip.

Re:Three chips in and Google Tensor is on life support by Symmetry on Thursday November 23, 2023 @10:24AM (#38393706)
A million element square matrix is a lot of data. To process that in a second is much more bandwidth than a single socket can support, so you'll need many sockets too.
Re:Three chips in and Google Tensor is on life support by bigbillheck on Thursday November 23, 2023 @08:33AM (#38392548)
> naive million by million matrix multipication....how do we reduce this to 1s

A matrix of that size in single precision is 32TB, a better question is how do you store it?

Re:Three chips in and Google Tensor is on life support by ForkMeOnTinder on Thursday November 23, 2023 @08:37AM (#38392586)
Re:Three chips in and Google Tensor is on life support by bigbillheck on Thursday November 23, 2023 @10:10AM (#38393536)
The original ask specified "naive million by million matrix multipication", I don't consider sparse matrices to be "naive".
Re:Three chips in and Google Tensor is on life support by tyingq on Thursday November 23, 2023 @06:07AM (#38391552)
This article seems fairly straightforward: https://maelfabien.github.io/bigdata/ColabTPU/