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GistNoesis an hour ago

What they need is not so much memory but memory bandwidth.

For training, their models have a certain number of memory needed to store the parameters, and this memory is touched for every example of every iteration. Big models have 10^12 (>1T )parameters, and with typical values of 10^3 examples per batch, and 10^6 number of iteration. They need ~10^21 memory accesses per run. And they want to do multiple runs.

DDR5 RAM bandwidth is 100G/s = 10^11, Graphics RAM (HBM) is 1T/s = 10^12. By buying the wafer they get to choose which types of memory they get.

10^21 / 10^12 = 10^9s = 30 years of memory access (just to update the model weights), you need to also add a factor 10^1-10^3 to account for the memory access needed for the model computation)

But the good news is that it parallelize extremely well. If you parallelize you 1T parameters, 10^3 times, your run time is brought down to 10^6 s = 12 days. But you need 10^3 *10^12 = 10^15 Bytes of RAM by run for weight update and 10^18 for computation (your 120 billions gigabytes is 10^20, so not so far off).

Are all these memory access technically required : No if you use other algorithms, but more compute and memory is better if money is not a problem.

Is it strategically good to deprive your concurrents from access to memory : Very short-sighted yes.

It's a textbook cornering of the computing market to prevent the emergence of local models, because customers won't be able to buy the minimal RAM necessary to run the models locally even just the inferencing part (not the training). Basically a war on people where little Timmy won't be able to get a RAM stick to play computer games at Xmas.

lysace 18 minutes ago | parent [-]

Thanks - but this seems like fairly extreme speculation.

> if money is not a problem.

Money is a problem, even for them.