π§ Key Elements of Training a Foundation Model
Training a foundation model involves three main stages:
1. Pre-trainingβ
- Purpose: Teach the model general capabilities and understanding of human language and multimodal data.
- Method:
- Uses self-supervised learning
- Trained on vast amounts of unstructured data (text, images, audio, etc.)
- Requirements:
- Trillions of tokens
- Petabytes of data
- Millions of GPU compute hours
- Significant trial and error
- Outcome:
The model learns fundamental patterns and representations but is not specialized for specific tasks or domains.
2. Fine-tuningβ
- Purpose: Adapt the pre-trained model to specific tasks or domains.
- Method: Uses supervised learning with labeled datasets to update the model's weights.
- Key Variants: Instruction tuning, domain adaptation, parameter-efficient fine-tuning (PEFT)
- Consideration: Risk of catastrophic forgetting when training on single tasks.
3. Continuous Pre-trainingβ
- Purpose: Extend the modelβs training with new general data to improve generalization or keep it up to date.
- Method:
Continues the original pre-training process, often on a broader or refreshed dataset. - Benefit:
Enhances the modelβs foundational knowledge without focusing on a specific task or domain.
Each stage builds upon the previous one β from general understanding (Pre-training) to task specialization (Fine-tuning) to refinement and updates (Continuous Pre-training).