Research-Stack/4-Infrastructure/shim/unsloth_physics_math_train.py
2026-05-11 22:18:31 -05:00

101 lines
3.6 KiB
Python

#!/usr/bin/env python3
"""Unsloth SFT scaffold for a physics/math routing LLM.
Use a trainable HF/safetensors Gemma-family checkpoint as --model-name. A GGUF
is a good deployment/teacher artifact, but this script expects a trainable
Transformers checkpoint because LoRA/QLoRA training needs model weights in that
ecosystem.
"""
from __future__ import annotations
import argparse
from pathlib import Path
def main() -> int:
parser = argparse.ArgumentParser()
parser.add_argument("--model-name", required=True, help="HF/Unsloth trainable model id or local safetensors dir")
parser.add_argument("--dataset", type=Path, default=Path("4-Infrastructure/shim/physics_math_llm_sft.jsonl"))
parser.add_argument("--out", type=Path, default=Path("4-Infrastructure/shim/physics_math_lora"))
parser.add_argument("--max-seq-length", type=int, default=4096)
parser.add_argument("--load-in-4bit", action="store_true")
parser.add_argument("--max-steps", type=int, default=120)
parser.add_argument("--learning-rate", type=float, default=2e-4)
parser.add_argument(
"--packing",
action=argparse.BooleanOptionalAction,
default=True,
help="Pack short SFT records to reduce padding waste; latest Unsloth/NVIDIA paths cache packed metadata.",
)
parser.add_argument("--dataset-num-proc", type=int, default=2)
args = parser.parse_args()
try:
from datasets import load_dataset
from trl import SFTTrainer, SFTConfig
from unsloth import FastLanguageModel
except ImportError as exc:
raise SystemExit(
"Missing training dependencies. Install Unsloth stack first, then rerun. "
"Expected: unsloth, trl, datasets."
) from exc
model, tokenizer = FastLanguageModel.from_pretrained(
model_name=str(args.model_name),
max_seq_length=args.max_seq_length,
dtype=None,
load_in_4bit=args.load_in_4bit,
)
model = FastLanguageModel.get_peft_model(
model,
r=16,
target_modules=["q_proj", "k_proj", "v_proj", "o_proj", "gate_proj", "up_proj", "down_proj"],
lora_alpha=16,
lora_dropout=0,
bias="none",
use_gradient_checkpointing="unsloth",
random_state=3407,
)
dataset = load_dataset("json", data_files=str(args.dataset), split="train")
def formatting_prompts_func(examples):
texts = []
for messages in examples["messages"]:
texts.append(tokenizer.apply_chat_template(messages, tokenize=False, add_generation_prompt=False))
return {"text": texts}
dataset = dataset.map(formatting_prompts_func, batched=True)
trainer = SFTTrainer(
model=model,
tokenizer=tokenizer,
train_dataset=dataset,
args=SFTConfig(
output_dir=str(args.out),
dataset_text_field="text",
max_seq_length=args.max_seq_length,
packing=args.packing,
dataset_num_proc=args.dataset_num_proc,
per_device_train_batch_size=1,
gradient_accumulation_steps=8,
warmup_steps=5,
max_steps=args.max_steps,
learning_rate=args.learning_rate,
logging_steps=5,
save_steps=max(20, args.max_steps // 2),
optim="adamw_8bit",
seed=3407,
),
)
trainer.train()
args.out.mkdir(parents=True, exist_ok=True)
model.save_pretrained(str(args.out))
tokenizer.save_pretrained(str(args.out))
print(f"saved LoRA adapter to {args.out}")
return 0
if __name__ == "__main__":
raise SystemExit(main())