llama 3.1 has correct max_seq_len for all versions

[akashc1]

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Please link to any issues this PR addresses. #2202

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What are the changes made in this PR?

• Ensure all llama 3.1 instantiations uses the correct max_seq_len the model was originally trained with based on the HF config

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[felipemello1]

thanks for the PR, do you mind updating the docstrings too, so they include the new arg? I think that for 405B the default is wrong, it should be 131k.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 23.85%. Comparing base (aa8f365) to head (d2f581c).

Additional details and impacted files

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  Lines       20658    20658           
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  Hits         4928     4928           
  Misses      15730    15730           

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[RdoubleA]

This seems inconsistent with our other builders, which do not specify a max seq len parameter. If you want to change the default max seq len for llama3_1 you should use the base builder llama3_1() instead of the 8b and 405b builders, as they're meant to expose minimal parameters and give all the defaults to get the correct model. But let us know if this is too prohibitive.

[akashc1]

@felipemello1 @RdoubleA thank you for the comments, can you please check the updated implementation? I set the correct default from the HF model config for Llama 3.1 models in the _model_builders file.

[felipemello1]

I am on PTO this week, but if Rafi doesnt approve it by next week, i will review it. @RdoubleA , you said "If you want to change the default max seq len for llama3_1 you should use the base builder llama3_1()", that is true, but if the model is the LoRA, this parameter is not exposed. IMO, all model parameters should be exposed in the lora builder. Do you disagree?

[ebsmothers]

Commented on the issue as well, but I think we should only change the llama3_1_405b and lora_llama3_1_405b builders here. If we change llama3_1 to hardcode max_seq_len it'd be inconsistent with our other models

[ebsmothers]

@akashc1 thanks for catching the bug. Do you want to push the changes I mentioned? (Basically your PR should just set max_seq_len=131072 in llama3_1_405b and lora_llama3_1_405b.) If not let me know and I can push to your PR.