Agent Platform Model Tuning Heuristics and Concepts
This guide details the core concepts of fine-tuning and provides heuristics for adjusting hyperparameters based on your specific dataset.
Core Tuning Concepts
Open Models Tuning Modes
- FULL: Updates all parameters of the model. Requires more GPU memory and a larger dataset to avoid catastrophic forgetting.
- PEFT_ADAPTER: Parameter-Efficient Fine-Tuning. Only a small set of "adapter" weights are trained. Faster, uses less memory, and is less prone to overfitting on small datasets.
Hyperparameters
- Epochs: Number of times the model sees the entire dataset.
- Learning Rate: Step size for optimization. Too high can cause instability; too low can lead to very slow convergence.
- Adapter Size (Rank): For PEFT_ADAPTER, this determines the capacity of the adapters. Higher rank allows more complex learning but increases the risk of overfitting.
Dataset Heuristics
The size and quality of your dataset should dictate your parameter choices. Refer to Models Catalog for baseline values, then adjust as follows:
1. Dataset Size Implications
| Dataset Size | Tuning Mode Recommendation | Learning Rate Adjustment | Epochs Recommendation |
|---|---|---|---|
| < 100 examples | PEFT_ADAPTER (Rank 8) | Lower than baseline | 1-2 |
| 100 - 1000 examples | PEFT_ADAPTER (Rank 16/32) | Baseline | 3 |
| > 1000 examples | FULL or PEFT_ADAPTER (Rank 32) | Higher than baseline | 3-5 |
2. General Best Practices
- Overfitting: If validation loss starts increasing while training loss decreases, you are overfitting. Reduce epochs or decrease the learning rate.
- Underfitting: If both training and validation loss remain high, increase the learning rate or use more epochs.
- Validation: Always use a validation set to monitor performance. If not provided, a 10% split is highly recommended; do not go above it, for the reason given in Data Preparation Guide.
- Checkpoints: The final model is always saved to
<output_uri>/postprocess/node-0/checkpoints/final.
Hardware and Limitations
For specific hardware recommendations and sequence length limits per model, please refer to the Models Catalog.