Training instability

[Taoboan1999]

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Question

I'm training yolov12's model on my own dataset, and on map50 of the validation set, I often get 0.67→0.68→0.69→0.70→0.71→0.68→0.67→0.67→0.68→0.67→0.67
Such approximate changes in results. I ensured maximum batchsize=8 and maximum image size, tried reducing the learning rate lr0=0.001→0.0001→0.00001, and increased the parameters for data augmentation (mosaic).

I can't change all the data in my training set and validation set, how can I change this bad status quo please

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[UltralyticsAssistant]

👋 Hello @Taoboan1999, thank you for reaching out and for your detailed description! 🚀 This is an automated response to help you get started, and an Ultralytics engineer will assist you soon.

Please visit our ⭐️ Tutorials for guidance, including quickstart guides for Custom Data Training and tips for Best Training Results.

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[pderrenger]

Hi @Taoboan1999! The training instability you're experiencing with oscillating mAP50 values (0.67-0.71) is common and can be addressed with several adjustments. Try implementing learning rate scheduling with --cos-lr for cosine annealing, reduce --momentum from default 0.937 to 0.9, and consider using --patience for early stopping to prevent overfitting. You might also benefit from using Exponential Moving Average (EMA) which smooths model weights during training and often leads to more stable convergence patterns.

[Taoboan1999]

Hi @Taoboan1999! The training instability you're experiencing with oscillating mAP50 values (0.67-0.71) is common and can be addressed with several adjustments. Try implementing learning rate scheduling with --cos-lr for cosine annealing, reduce --momentum from default 0.937 to 0.9, and consider using --patience for early stopping to prevent overfitting. You might also benefit from using Exponential Moving Average (EMA) which smooths model weights during training and often leads to more stable convergence patterns.

Thank you very much for your patience, I will try the various methods you mentioned one by one and if any of them are more effective, I will post them

[Taoboan1999]

Hi @Taoboan1999! The training instability you're experiencing with oscillating mAP50 values (0.67-0.71) is common and can be addressed with several adjustments. Try implementing learning rate scheduling with --cos-lr for cosine annealing, reduce --momentum from default 0.937 to 0.9, and consider using --patience for early stopping to prevent overfitting. You might also benefit from using Exponential Moving Average (EMA) which smooths model weights during training and often leads to more stable convergence patterns.

How do you turn on EMA in yolov12 training.

[pderrenger]

Hi @Taoboan1999! EMA is enabled by default in YOLOv5 training - you can control it with the --ema flag (enabled by default) and adjust the decay rate using --ema-decay (default 0.9999). If you want to disable EMA for testing, use --ema False, or to modify the decay rate for potentially more stable training, try --ema-decay 0.999 for faster adaptation to recent weights.

[Taoboan1999]

Hi @Taoboan1999! EMA is enabled by default in YOLOv5 training - you can control it with the --ema flag (enabled by default) and adjust the decay rate using --ema-decay (default 0.9999). If you want to disable EMA for testing, use --ema False, or to modify the decay rate for potentially more stable training, try --ema-decay 0.999 for faster adaptation to recent weights.

Thank you again for your answer. I will try modifying this parameter when training YOLOv5, but I am still encountering overfitting issues in YOLOv12. I will ask a question in the YOLOv12 issues section. Thank you.

[pderrenger]

You're welcome @Taoboan1999! Just to clarify, this is the YOLOv5 repository, so for YOLOv12 (YOLO12) questions you'll want to head over to the main Ultralytics repository where the newer YOLO versions are maintained. Good luck with your training!