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Comment by newswasboring | Hacker News Reader

The intention behind it is pretty good. Best of luck to them.

I wonder if I can donate computing power to this remotely. Like the old SETI or protein folding things. Use idle CPU to calculate for the network. Otherwise the estimates I have seen on how much it would take to train these models are enormous.

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Not directly related, but the Learning@home [1] project aims to achieve precisely that goal of public, volunteer-trained neural networks. The idea is that you can host separate "experts," or parts of your model (akin to Google's recent Switch Transformers paper) on separate computers.

This way, you never have to synchronize the weights of the entire model across the participants — you only need to send the gradients/activations to a set of peers. Slow connections are mitigated with asynchronous SGD and unreliable/disconnected experts can be discarded, which makes it more suitable for Internet-like networks.

Disclaimer: I work on this project. We're currently implementing a prototype, but it's not yet GPT-3 sized. Some issues like LR scheduling (crucial for Transformer convergence) and shared parameter averaging (for gating etc.) are tricky to implement for decentralized training over the Internet.

[1] https://learning-at-home.github.io/

Do you have a personal Twitter account I can follow? Your career is one I'd like to follow.

Sure! It's @m_ryabinin

Thanks! :D

Your project looks so interesting. Have u thught of putting the experts on a distributed market where their expertise and work can be exchanged for some token (obvlsy using a blockchain).

This would encourage people to host experts in your network and would create value.

Thank you! This is definitely something we should look into in the future (hopefully with community help); as of now, training infrastructure and model convergence are the highest priorities. That said, we welcome all ideas of ways to motivate more volunteers to join the experiments, because Learning@home team comes from a distributed DL background with limited volunteer computing expertise.

Also, I believe that for some projects (e.g. GPT-3 replication effort) people would want to join the network regardless of the incentive mechanism, as demonstrated by Leela Chess Zero [1].

[1] http://lczero.org/

How do you deal with adversarial/byzantine updates that attempt to degrade performance or even install a backdoor? Do you use plain averaging, or some other aggregation algorithm like Multi-Krum?

This is also what I was thinking about. Considering that making up bad data does not require any GPU work as opposed to honest calculating nodes, the model can fall quickly if without taking some measures to deal with them (adverserial nodes).

A draft solution would be for the central server to measure the goodness of each update and drop the ones that don't perform well. This could somehow work since inference is much cheaper than gradients computing.

For now, the only separation we have is that each worker is responsible for its own weights, since network security has not been our top priority. Still, we've been thinking about adding some security measures like proof-of-work for each node and detection of anomalous inputs/gradients (or simply NaN values). Right now we're running experiments on internal hardware, but before a public launch we'll make sure that malicious participants won't put everybody else's work to waste :)

The primary issue is that large scale GPU training is primarily dominated by communication costs. Since to some approximation things need to be synchronized after every gradient update, it becomes very quickly quite infeasible to increase the communication cost.

Yeah! sounds great, if I could easily run a SETI-at-home style thing to contribute to training a (future) model similar to GPT-x, but with the result freely available to play with, I reckon i'd do it. Could even be made into a game I'd say! I am totally aware that gpt3 itself can't be run on a regular workstation, but maybe hosting for instances of models from the best/most-interesting training runs could be worked out by crowd-funding?

I was just gonna propose something like this. Democratizing large ML models.

They get this suggestion a lot. There's a section in their FAQ that explains why it's infeasible.

https://github.com/EleutherAI/info

TensorFlow supports distributed training with a client server model.

Does it also solve the problem of everyone having different hardware?

It does.

For most models, your home broadband would be far too slow though.

Is it because they will have to communicate back errors during training? I forgot that training these models is more of a global task than proteins folding. In that sense this is less parallelizable over the internet.

Yes, and also activations if your GPU is too small to fit the whole model. The minimum useful bandwidth for that stuff is a few gigabits...

What about some kind of sharding, parts of the computation that could be executed in isolation for a longer period of time?

An ongoing research problem. OpenAI would certainly like being able to use smaller GPUs, instead of having to fit the entire model into one.

GPT-3 does not fit in any one GPU that exists at present. It's already spread out across multiple GPUs.

You're a genius! How do we get this started. Wouldn't there be so many bitcoin rigs already that could be used for this already?

I'd be very willing to spend time and money on this!

Could someone set up a chat room or something?

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