SFT with Gold Data (SFT)#
SFT supervised finetunes a decoder using ground-truth <chat_history, question, passage, answer> pairs (for one turn QA, you can use chat_history=''
). This is a simple yet effective method to adapt a model toward a specific task. Under the hood, this training script:
concatenates the
chat_history
,question
, andpassage
into a single inputtrains the model to mimic the ground-truth
answer
using standard cross-entropy loss
Running SFT Trainer#
At a high level, SFT training requires:
a training, evaluation, and test dataset of <question, passage, answer> pairs
a generative model (e.g.
mistralai/Mistral-7B-Instruct-v0.2
) to be trainedan embedding model (e.g.
intfloat/e5-base-v2
) used for automatic E2E evaluation during training
Once you gathered these pieces, simply run:
python scripts/train/qa_llm/train_w_gt.py \
--use_flash_attention true \
--per_device_train_batch_size 4 \
--per_device_eval_batch_size 4 \
# other training hyperparameters omitted
--model_name_or_path mistralai/Mistral-7B-Instruct-v0.2 \
--assistant_prefix [/INST] \
--user_prefix "<s>[INST]" \
--sep_user " " \
--sep_sys "</s>" \
--eval_embedding_model intfloat/e5-base-v2 \
--output_dir model_checkpoints/my_SFT_qa_model \
--train_file <example/train_w_qa.jsonl> \
--eval_file <example/eval_w_qa.jsonl> \
--test_file <example/test_w_qa.jsonl> \
--full_dataset_file_path <example/documents.pkl> \
--full_dataset_index_path <example/index>
for a full list of arguments, you can run python scripts/train/qa_llm/train_w_gt.py -h
. In this example:
--per_device_train_batch_size
,--model_name_or_path
, and other training arguments are from the HuggingFace TrainingArguments class. Since we implement our trainers from Huggingface’s Trainer class, it is compatible with most of the arguments there.--assistant_prefix
and--user_prefix
are the prefixes used to format the conversation history. This can be specific to the model you are training on (e.g.,mistralai/Mistral-7B-Instruct-v0.2
)--eval_embedding_model
is used during evaluation to compute the E2E evaluation metrics--output_dir
is the directory where the trained model, training history, and evaluation results will be saved--train_file
,--eval_file
, and--test_file
are the paths to the training, evaluation, and test datasets. See RQA Data Format for more details on the format of these files.--full_dataset_file_path
and--full_dataset_index_path
are the paths to the documents and their indices. This is used byeval_embedding_model
to perform retrieval during evaluation. See RQA Data Format for more details on the format of these files.
Note
For complete examples (e.g., obtaining files like <example/train_w_qa.jsonl>
or other training hyperparameters), you can use Databricks and Faire as references.