YOLOv5 tqdm progress bar multi-line output bug

[glenn-jocher]

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  • exception-raising bug
  • visual output bug
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  read the [known issues]
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We use tqdm extensively in YOLOv5 https://github.com/ultralytics/yolov5, and most of the time it works great!

Sometimes it will start outputting a new line per progress bar update though, which causes many problems. This is especially prevalent (100% occurrence rate) when running in a Docker image after some time, or running a Docker image in detached mode:

YOLOv5 🚀 v6.1-25-gcaf7ad0 torch 1.11.0 CPU

# Run latest YOLOv5 Docker Image
t=ultralytics/yolov5:latest && sudo docker pull $t && sudo docker run -it $t

# inside Docker container start training YOLOv5 model
python train.py

Our exact tqdm implementation is here:
https://github.com/ultralytics/yolov5/blob/caf7ad0500f8fc58567a7aa01ca91d5ee77691d6/train.py#L302-L308

        pbar = tqdm(pbar, total=nb, bar_format='{l_bar}{bar:10}{r_bar}{bar:-10b}')  # progress bar
        for i, (imgs, targets, paths, _) in pbar:
            # do stuff 

I've tried everything I can think of, including defining a format (shown above), defining a fixed terminal size, using the default settings, and this problem still occurs every time. Any ideas for how we can fix this?

[casperdcl]

Interesting, I can't reproduce this. Works fine (progress is on one line):

docker run -it tqdm/tqdm python -c 'from tqdm import trange; [0 for _ in trange(int(1e8))]'

Related: #771?

[thomassajot]

This issue is still relevant.
Happens on TMUX or Bash, Ubuntu 18, python 3.9. How can we investigate ?

[niko-zvt]

This issue is still relevant.
Happens with Jupyter Notebook, python 3.10.

[glenn-jocher]

Yes, still happens for us in YOLOv5. Also happens in our GitHub CI runners, i.e. see:
https://github.com/ultralytics/yolov5/actions/runs/4218882205/jobs/7323729521