3 ms·
Yes exactly, I fear that shortening the training time would skew the results. In the very short term, smaller batch size is typically better just because you ne
by spi 10mo ago
Yes exactly, I fear that shortening the training time would skew the results. In the very short term, smaller batch size is typically better just because you need a certain amount of gradient updates to move away from the original random, hence pretty terrible, weight distribution. Larger batch size gives a steadier, but slower, convergence, so it's hard to say for sure what is better for a given compute budget.
I'm definitely _not_ encouraging you on spending more money on a side topic just for the sake of optimizing this one parameter, there will always be another parameter after that that you'll feel an urge to optimize :-) I'd say it's already a pretty neat result to have come to a very close score to the original GPT2 training starting from scratch!
P.S. If you want to push it a bit further, rather than optimizing parameters for this model, last week at EurIPS I heard that a current "very good" modern repo to start from in order to train a good LLM is this: https://github.com/Niccolo-Ajroldi/plainLM https://github.com/Niccolo-Ajroldi/plainLM. I haven't investigated this exactly (I'm not working on LLM), but it might be interesting to you for a sample run. The (N)EurIPS paper that was discussed at the conference claimed that the only important change to do was to modify the hyperparameters of the Adam optimizer, setting beta1=beta2=0.95 for example (the default values are beta1=0.9 and beta2=0.999 which are apparently outdated).
- gpjt 10mo agoAwesome, thanks! I'm still doing trains on the big machines right now (hopefully will write up over xmas) but I think once I've worked out the sweet spot for memgatokens per dollar for this model, it's time to start tweaking the other controls -- LR and cosine variation of it, as you said, and also dropout, bias, weight tying, and definitely gradient clipping (which should at least get better bang for the buck from time/$ spent). I'll leave it to Google to follow up Chinchilla with a "best batch size across a thousand trained models" paper ;-)