[Feature Request] Hybrid Training Approach

[Dalhimar]

Implement Hybrid Approach for Sequential and Length-Based Batching in Training

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Description

Context and Motivation:
Currently, the Training PRO extension offers the capability to group samples by length, optimizing computational efficiency during training. However, this method can disrupt the sequential flow of conversations, impacting the model's ability to comprehend the progression and context of dialogues. To address this, I propose a new feature: a Hybrid Training Approach that combines the efficiency of length-based batching with the contextual learning benefits of sequential data feeding.

Proposed Feature:
A Hybrid Training Approach that initially uses length-based batching and then transitions to sequential feeding. This approach aims to balance computational efficiency with the need for the model to learn and understand the natural flow and context of conversations.

Implementation Details:

1. Initial Phase - Length-Based Batching:

   • In the initial stages of training, group exchanges by length to maximize batch uniformity and computational efficiency.
   • This phase focuses on learning basic language structures, grammar, and context-independent response generation.

2. Transition Phase - Introduce Sequential Elements:

   • Gradually introduce batches that maintain the sequential order of exchanges within conversations.
   • This phase starts to incorporate the understanding of conversation flow and context.
   • This could be done by simply grouping two seqequential entries together and treating them as a single sample for batching.

3. Final Phase - Sequential Feeding:

   • In the later stages of training, fully transition to feeding data in its original sequential order, respecting conversation and message sequence.
   • Focus on refining the model's ability to comprehend and generate contextually coherent and relevant responses.

4. Configurable Parameters:

   • 1. Epoch-Based Transition:
     • Users can specify the number of epochs after which the training should transition from length-based batching to sequential feeding.
     • Example: Transition after 10 epochs of length-based training.
   • 2. Loss Threshold for Transition:
     • Set a specific loss value threshold that triggers the transition. Once the model's training loss falls within this range, the training method switches to sequential feeding.
     • Initial Proposal: Transition when the loss value falls between 2.0 and 2.5. This range indicates that the model has achieved a basic understanding of language structures and is ready for more context-focused learning. If a secondary transition is implemented, I propose a loss range of 1.5 to 2.
   • 3. Step-Based Transition:
     • Define the transition in terms of the number of training steps. This can be useful for fine-grained control over the training process.
     • Example: Transition after 20,000 steps of length-based training.

5. Monitoring and Evaluation:

   • Implement monitoring tools to evaluate the performance impact of each phase.
   • Track metrics specific to context understanding and conversation coherence.

Benefits:

• Balances computational efficiency and the model’s ability to understand conversation context.
• Allows the model to first grasp basic language constructs before focusing on complex contextual relationships.
• Provides flexibility to users to tailor the training process based on model requirements and computational resources.

Possible Challenges:

• Determining the optimal point or criteria for transitioning between phases.
• Ensuring that the model does not lose its grasp on basic language understanding while focusing on contextual aspects.

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Reasoning

Why Start with Length-Based Batching?

In the initial stages of training, our primary goal is to familiarize the model with the basic structures of language—grammar, common phrases, and simple dialogue patterns. Length-based batching is highly efficient for this purpose, as it groups exchanges of similar length together, allowing for more uniform and faster processing. This approach helps the model quickly learn fundamental language patterns, which is crucial for establishing a baseline understanding.

The Transition to Sequential Data Feeding

Once the model has reached a certain level of proficiency (as indicated by predetermined metrics like epochs, loss values, or training steps), I propose transitioning to sequential data feeding. This phase is critical for several reasons:

1. Contextual Understanding: Sequential data feeding allows the model to see conversations as they naturally occur. This helps the model understand how ideas and dialogue flow over a series of exchanges, which is key to generating coherent and contextually appropriate responses.

2. Long-Term Dependency Learning: By following the natural progression of conversations, the model learns to recognize and remember information from earlier in the conversation (long-term dependencies). This is essential for tasks like question answering, where context from the entire conversation can influence the response.

3. Realistic Interaction Simulation: Sequential training better simulates real-world interactions, where responses depend not just on the immediate prompt but on the entire conversation history. This is especially important for models expected to perform in conversational AI settings, where maintaining context is crucial.

4. Nuanced Language Learning: As conversations evolve, they often grow in complexity and subtlety. Sequential data feeding exposes the model to this natural evolution, teaching it to understand and generate more nuanced and sophisticated language use.

Balancing Efficiency and Depth

The Hybrid Approach aims to balance the need for computational efficiency with the depth of learning required for a high-performing conversational AI model. By starting with length-based batching, we maximize our training speed and efficiency. Then, by transitioning to sequential data feeding, we ensure the model develops a deep, contextual understanding of language, which is vital for advanced AI applications.

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Additional Notes:

This feature is expected to enhance the versatility of the training extension, making it suitable for a wider range of applications, especially those requiring a strong understanding of conversational context. User feedback and iterative testing will be crucial in refining this feature.

The transition could be done in either the two stage method mentioned, or in a single stage where it switches to fully sequential data feeding.