Update torch.cuda.amp to torch.amp

[jacobdbrown4]

torch.cuda.amp is deprecated as of Pytorch 2.4. This PR updates use to torch.amp. This gets rid of the

FutureWarning: `torch.cuda.amp.autocast(args...)` is deprecated. Please use `torch.amp.autocast('cuda', args...)` instead.
  with torch.cuda.amp.autocast(amp):

warning as mentioned in #13226.

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Update to use latest CUDA AMP (Automatic Mixed Precision) API across various files for better compatibility and performance.

📊 Key Changes

• Replaced torch.cuda.amp.autocast with torch.amp.autocast("cuda") in multiple files.
• Replaced torch.cuda.amp.GradScaler with torch.amp.GradScaler("cuda").

🎯 Purpose & Impact

• Improved Compatibility: Ensures that the code remains compatible with the latest PyTorch changes, reducing the risk of future issues.
• Performance: Leverages CUDA's improved automatic mixed precision to potentially enhance computational efficiency.
• Maintenance: Simplifies code adjustments related to AMP, making future updates easier to manage.

[github-actions]

All Contributors have signed the CLA. ✅
_{Posted by the CLA Assistant Lite bot.}

[github-actions]

👋 Hello @jacobdbrown4, thank you for submitting a YOLOv5 🚀 PR! To allow your work to be integrated as seamlessly as possible, we advise you to:

• ✅ Verify your PR is up-to-date with ultralytics/yolov5 master branch. If your PR is behind you can update your code by clicking the 'Update branch' button or by running git pull and git merge master locally.
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• ✅ Reduce changes to the absolute minimum required for your bug fix or feature addition. "It is not daily increase but daily decrease, hack away the unessential. The closer to the source, the less wastage there is." — Bruce Lee

[jacobdbrown4]

I have read the CLA Document and I sign the CLA

[jacobdbrown4]

recheck

[glenn-jocher]

@jacobdbrown4 thank you for your comment! To ensure we address your issue effectively, could you please verify that you are using the latest versions of YOLOv5 and all related dependencies? This helps us confirm whether the problem persists with the most recent updates.

If the issue is still reproducible, please provide additional details such as error messages, steps to reproduce, and any relevant code snippets. This information will help us diagnose and resolve the issue more efficiently.

Looking forward to your response! 😊

[ijnrghjkdsmigywneig203]

This pull request needs to be merged, inference times are slower due to this error constantly popping up with the newest versions of pytorch.

[ijnrghjkdsmigywneig203]

@glenn-jocher

[glenn-jocher]

Thank you for your input. Please ensure you're using the latest YOLOv5 version to see if the issue persists. If the problem continues, provide additional details so we can assist further.

[mezotaken]

Reproducible with this commit 907bef2
Enough to run python3 train.py and it will spam this warning on every iteration

[pderrenger]

Please ensure you're using the latest YOLOv5 version, as updates may resolve this issue. If it persists, let us know with more details.

[ijnrghjkdsmigywneig203]

Are you guys just bots designed to repeat the same thing when a real issue is present within the code? The latest version of yolov5 is literally fetched every single time I initialize my script. The issue is with your code being outdated.

[pderrenger]

@ijnrghjkdsmigywneig203 thank you for your feedback. We recommend ensuring all dependencies are up-to-date. If the issue persists, please provide more details so we can investigate further.

[ijnrghjkdsmigywneig203]

Everything is up to date and the error for your outdated code still occurs. What can I do to solve it?

torch.cuda.amp is deprecated as of Pytorch 2.4. This PR updates use to torch.amp. This gets rid of the

FutureWarning: torch.cuda.amp.autocast(args...) is deprecated. Please use torch.amp.autocast('cuda', args...) instead.
with torch.cuda.amp.autocast(amp):

[pderrenger]

Thank you for bringing this to our attention. Please check if there's an open pull request addressing this update. If not, consider submitting one to help resolve the issue.

[beltoforion]

There is an open pull request regarding this issue that will solve it. It is this one. Please merge this PR.

[pderrenger]

Thank you for pointing this out. Please follow the pull request for updates, as it will be reviewed and merged if it meets the requirements.

[ijnrghjkdsmigywneig203]

@glenn-jocher

[sakgoyal]

will this be merged anytime soon?

[pderrenger]

Thank you for following up. The PR appears to address the deprecation warning for torch.cuda.amp in PyTorch 2.4. I'll let the maintainers review and make a decision on merging. In the meantime, you can track the PR status for updates.