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DeepMind achieves SOTA image recognition with 8.7x faster training

arxiv.org

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Re: DeepMind achieves SOTA image recognition with 8.7x faster training

#51

I have a feeling the ML community is going to pivot focus to faster and smaller training before larger advancements are made. It's simply too expensive for much AI research to happen when state of the art models take 500k of hardware to train. For all the mathematician hype around ML research, much of the work is closer to alchemy than science. We simply don't understand a great deal of why these neural nets work. Th…

There's a lot of interest in various ML communities on more efficient training and inference. Both vision and NLP have had a growing focus on these problems in recent years.

I think you make a good observation that much of ML progress is driven by tinkering with existing models, though instead of describing it as more "alchemy than science" it's probably more accurate to say it's very experimental right now. Being very experimental is neither unscientific nor unusual in the development of knowledge. James Watt worked as an instrument maker (not a theoretician) when he invented the Watt steam engine in 1776 [1], and at the time the idea of heat as Phlogiston [2] was still more prevalent than anything that looks like modern thermodynamics. Theory and practice naturally take turns outpacing each other, which is part of why we need both.

I'd also caution against the belief that experimental work doesn't require "particularly demanding thought". There are many things one can tweak in current ML models (the search space is exponential) and, as you point out, the experiments are expensive. Having a solid understanding of the system, great intuition, and good heuristics is necessary to reliably make progress.

For those who are interested in the theory of deep learning, the community has recently made great strides on developing a mathematical understanding of neural networks. The research is still very cutting edge, but the following PDF helps introduce the topic [3].

[1]: https://en.wikipedia.org/wiki/James_Watt

[2]: https://en.wikipedia.org/wiki/Phlogiston_theory

[3]: https://www.cs.princeton.edu/courses/archive/fall19/cos597B/...

Re: DeepMind achieves SOTA image recognition with 8.7x faster training

#52

Earlier quoted context omitted.

In cases where you have to deploy the model and you are limited in terms of flops, this paper does not help much, unless it’s removal of batchnorm somehow allows a future network that is actually faster at inference time.

There are a lot of techniques for sparsifying or pruning or distilling models to reduce inference FLOPS, and they almost always produce better results when starting with a better model. Also, if your model is 8x faster to train at the same size then you can do 8x as much hyperparameter tuning and get a better result.

This model is much more expensive than efficientnet at inference (I think the flops are about 2x?). You can use these same techniques with efficientnet.

Re: DeepMind achieves SOTA image recognition with 8.7x faster training

#53
post #5

tl;dr: Don't use batch norm for preventing exploding gradients but adaptive gradient thresholds. For this they compute the Frobenius norm (square root of the sum of squares) of the weight layer and its gradient and take the ratio of these as clipping threshold. That saves the meta search for the optimal threshold but also is better than a fixed threshold could ever be. Very simple idea.

Lol, why is my comment down here with 7 upvotes.

Re: DeepMind achieves SOTA image recognition with 8.7x faster training

#54

I have a feeling the ML community is going to pivot focus to faster and smaller training before larger advancements are made. It's simply too expensive for much AI research to happen when state of the art models take 500k of hardware to train. For all the mathematician hype around ML research, much of the work is closer to alchemy than science. We simply don't understand a great deal of why these neural nets work. Th…

This feels much like the sentiment in the field about two years ago or so. While I feel like the "alchemy" storyline is still somewhat in play, most of the big important parts of the deep learning process have enough ideological linear approximators stacked around them that if you know what you're doing or looking at, you can jump to an unexplored trench with some reasonable feeling about whether you'll get something good or not. I feel like the "alchemy" approach is when people new to the field are innundated with information about it, and while I think that still holds, there very much is a well-understood science of principles in most parts of it.

There's the neural tangent kernel work that's achieved a lot, and the transformers themselves are really taking off a lot as the blockwise/lower rank approximation algorithms look more and more like circuits built off of basic, more well-established components.

"An average Joe could probably write influential ML papers by gluing RNN/GAN layers to existing models and fiddling with the parameters until they beat current state of the art. In fact, in NLP models, this is essentially what has happened with roBERTa, XLNET, ELECTRA, etc. They're all somewhat trivial variations on Google's BERT, which is more creative but yet again built on existing models."

This feels like it trivializes a lot of the work and collapses some of the major advancements in training at scale down to a more one-dimensional outlook. Companies are doing both, but it's easy to throw money and compute at an absolutely guaranteed logarithmic improvement in results. It's not stupidity, it's just reducing variance in scaling known laws as we work on making things more efficient, which weirdly enough starts the iterative process of academics frantically trying to mine the expensive, inefficient compute tactics to flag plant their own materials.

With respect to you comment on protein folding and such, I feel you might have missed a lot of the major work in that aren more recently. There really and truly been some field-shattering work on that in combining deep learning systems with last-mile supervision and refinement systems. I'd posit that we're very much out of the wild west and in the mild, but still rambunctious west, if I were to put terms on it.

With reference to guess and check -- yes, that especially was prevalent and worked 2-3 years ago and I'd be in favor of advocating that it does still happen somewhat in a more refined fashion, but I personally believe we'd not get too far beyond the SOTA if we're not working (effectively) with your data manifold now and tightly incorporating whatever projections/constraints of that data distillation process into your network training procedure. I really do agree with you in that I think average Joe breakthroughs will happen and continue to benefit the the field, and I'd certainly agree that there's always going to be the mediocre paper churn of paper mills I think that you alluded to trying to justify their own existence as academics/paper writers, but I really do legitimately think there's enough precedent set in most parts of the field that you need to have some kind of thoughtful improvement to move forward (like AdaBelief, which is still terrible because they straight up lie about what they do in the abstract, even though the improvement of debiasing the variance estimates during training is an exceptionally good idea).

Just my 2c, hope this helps. I think we may have a similar end perspective from two different sides, like two explorers looking at the same peak from the different side of the mountain. :thumbsup:

Re: DeepMind achieves SOTA image recognition with 8.7x faster training

#55

I have a feeling the ML community is going to pivot focus to faster and smaller training before larger advancements are made. It's simply too expensive for much AI research to happen when state of the art models take 500k of hardware to train. For all the mathematician hype around ML research, much of the work is closer to alchemy than science. We simply don't understand a great deal of why these neural nets work. Th…

Apply to TFRC! https://www.tensorflow.org/tfrc They are very permissive. And you get to play with $500k worth of hardware. Been a member for over a year now. Jonathan is singlehandedly the best support person I've ever worked with, or perhaps ever will work with. I would've completely agreed with you if not for TFRC. And I couldn't resist the opportunity of playing with some big metal, even if it's hard to work with.

just applied. thanks for sharing!

Re: DeepMind achieves SOTA image recognition with 8.7x faster training

#56
post #47

Earlier quoted context omitted.

No it hasn't https://paperswithcode.com/sota/image-classification-on-imag...

> No it hasn't https://paperswithcode.com/sota/image-classification-on-imag ... We were talking about models trained on ImageNet, specifically about the trade-off between accuracy and FLOPs. But the higher-accuracy models listed in your link use extra data. So it's not quite the same benchmark we were talking about.

The deepmind paper NFNet-F4+ you were talking about also has external training data.

The number one in accuracy (Meta pseudo labels) is also faster for inference (390M vs 570M parameters) vs the deepmind one. So what are you disagreeing with?

Re: DeepMind achieves SOTA image recognition with 8.7x faster training

#57

I was skeptical of the 83%-whatever top-1 accuracy on Imagenet. But someone pointed out that the accuracy increases when the model is pretrained on JFT, google's proprietary 100-million image dataset, the model's accuracy increases to 87%-whatever. That's pretty interesting. It implies that the original accuracy rating might be legit. The concern is that we're chasing the imagenet benchmark as if it's the holy grail,…

That’s awesome! Is your model available publically? I run a site [0] where users can generate images from text prompts using models like the official BigGAN-Deep one and I’d love to try it out for this purpose. Do you also have somewhere whereupon discuss this stuff? I’m new to ML in general and was wondering if there’s somewhere where y’all experts gather.

[0]: https://dank.xyz

Re: DeepMind achieves SOTA image recognition with 8.7x faster training

#59

I have a feeling the ML community is going to pivot focus to faster and smaller training before larger advancements are made. It's simply too expensive for much AI research to happen when state of the art models take 500k of hardware to train. For all the mathematician hype around ML research, much of the work is closer to alchemy than science. We simply don't understand a great deal of why these neural nets work. Th…

> The people doing math above algebra are few and the scene is dominated by "guess and check" style model tinkering.

"guess and check" is terribly ineffective with multi-day training runs. Brings us right back to the batch processing paradigm of the 1960s.

Re: DeepMind achieves SOTA image recognition with 8.7x faster training

#60

Earlier quoted context omitted.

While I generally agree to some extent: roBERTa, XLNET, ELECTRA, etc. They're all somewhat trivial variations on Google's BERT, which is more creative Researchers take inspirations from existing models of course and some BERT derivatives are trivial. However, XLnet is in it's own league, while the author (a genius chinese student) was inspired by BERT it is one of the few SOTA pré trained models to be not based on BE…

Interesting, but in not sure you're completely right about XLNET. I heard it takes an absurd amount of resources to train. Even more than the BERT variations. And this is likely why there's not a ton of interest in it

https://github.com/renatoviolin/xlnet XLnet running on very low end hardware (a single 8GB 2080 non ti) significantly outperform BERT large on e.g the reference question answering benchmarck: SQUAD 2 86% vs 81%

Nobody has even tried to create a spanXLnet (akin to spanBERT) How many years will be wasted before researchers get out of the BERT local minima? I'm a afraid it might last a decade

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