Support adamw_torch_8bit

[fzyzcjy]

What does this PR do?

Fixes #34893

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• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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[Rocketknight1]

cc @muellerzr

[fzyzcjy]

@muellerzr Hi is there anything I need to update in this PR?

[SunMarc]

Thanks for this PR @fzyzcjy ! LGTM ! Did you verify that this optimizer works (memory saving + training time ) as expected when using Trainer ?

[fzyzcjy]

Did you verify that this optimizer works (memory saving + training time ) as expected when using Trainer ?

I tried it before by subclassing and hacking Trainer before creating issue/PR, and yes it seems to work for me.

[HuggingFaceDocBuilderDev]

The docs for this PR live here. All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

[ArthurZucker]

Thanks for adding! 🤗

[fzyzcjy]

You are welcome!