SetMD's picture
Complete package: 18 experts + full codebase
ae1e90a
Raw History Blame Contribute Delete
11.9 kB
"""
Training script for the Shared Encoder
This script trains the encoder on a mixed corpus from all domains.
The encoder is trained once and then frozen for expert training.
Usage:
python train.py --data_dir ../../data --output_dir ../../experts --epochs 10
"""
import os
import argparse
import json
from pathlib import Path
from typing import Dict, List
import torch
import torch.nn as nn
from torch.utils.data import Dataset, DataLoader
from torch.optim import AdamW
from torch.optim.lr_scheduler import CosineAnnealingLR
from transformers import AutoTokenizer
from tqdm import tqdm
import wandb
from model import create_encoder, ContrastiveLoss
class MixedCorpusDataset(Dataset):
"""Dataset that combines samples from all expert domains."""
def __init__(
self,
data_dir: Path,
tokenizer,
max_length: int = 512,
samples_per_expert: int = 5000
):
self.tokenizer = tokenizer
self.max_length = max_length
self.samples = []
print("Loading datasets from all expert domains...")
# Load samples from each expert's data
expert_dirs = sorted([d for d in data_dir.iterdir() if d.is_dir()])
for expert_dir in tqdm(expert_dirs, desc="Loading experts"):
metadata_path = expert_dir / "metadata.json"
if not metadata_path.exists():
continue
with open(metadata_path) as f:
metadata = json.load(f)
# Skip synthetic datasets
if metadata.get("synthetic", False):
continue
# Load raw datasets
expert_samples = self._load_expert_data(expert_dir, samples_per_expert)
# Add domain label
for sample in expert_samples:
sample["domain"] = metadata["expert_id"]
self.samples.extend(expert_samples)
print(f"Loaded {len(self.samples)} total samples from {len(expert_dirs)} domains")
def _load_expert_data(self, expert_dir: Path, max_samples: int) -> List[Dict]:
"""Load samples from an expert's raw datasets."""
from datasets import load_from_disk
samples = []
raw_datasets = sorted(expert_dir.glob("raw_*"))
for raw_path in raw_datasets:
try:
dataset = load_from_disk(str(raw_path))
# Extract text from various dataset formats
for item in dataset:
text = self._extract_text(item)
if text and len(text) > 20: # Minimum length filter
samples.append({"text": text})
if len(samples) >= max_samples:
break
if len(samples) >= max_samples:
break
except Exception as e:
print(f" Warning: Could not load {raw_path}: {e}")
continue
return samples[:max_samples]
def _extract_text(self, item: Dict) -> str:
"""Extract text from various dataset formats."""
# Try common text fields
for field in ["text", "sentence", "question", "document", "article", "code"]:
if field in item and item[field]:
return str(item[field])
# For QA datasets
if "question" in item and "context" in item:
return f"{item['question']} {item['context']}"
# For summarization
if "article" in item:
return item["article"]
# Fallback: convert entire item to string
return str(item)
def __len__(self):
return len(self.samples)
def __getitem__(self, idx):
sample = self.samples[idx]
# Tokenize
encoding = self.tokenizer(
sample["text"],
max_length=self.max_length,
padding="max_length",
truncation=True,
return_tensors="pt"
)
return {
"input_ids": encoding["input_ids"].squeeze(0),
"attention_mask": encoding["attention_mask"].squeeze(0),
"domain": hash(sample["domain"]) % 1000 # Simple domain label
}
def train_epoch(
model: nn.Module,
dataloader: DataLoader,
optimizer: torch.optim.Optimizer,
criterion: nn.Module,
device: torch.device,
epoch: int
) -> float:
"""Train for one epoch."""
model.train()
total_loss = 0
pbar = tqdm(dataloader, desc=f"Epoch {epoch}")
for batch_idx, batch in enumerate(pbar):
input_ids = batch["input_ids"].to(device)
attention_mask = batch["attention_mask"].to(device)
labels = batch["domain"].to(device)
# Forward pass
embeddings = model(input_ids, attention_mask)
# Compute loss
loss = criterion(embeddings, labels)
# Backward pass
optimizer.zero_grad()
loss.backward()
# Gradient clipping
torch.nn.utils.clip_grad_norm_(model.parameters(), max_norm=1.0)
optimizer.step()
# Track metrics
total_loss += loss.item()
avg_loss = total_loss / (batch_idx + 1)
pbar.set_postfix({"loss": f"{avg_loss:.4f}"})
# Log to wandb
if batch_idx % 100 == 0:
wandb.log({
"train/loss": loss.item(),
"train/avg_loss": avg_loss,
"train/epoch": epoch
})
return total_loss / len(dataloader)
@torch.no_grad()
def validate(
model: nn.Module,
dataloader: DataLoader,
criterion: nn.Module,
device: torch.device
) -> float:
"""Validate the model."""
model.eval()
total_loss = 0
for batch in tqdm(dataloader, desc="Validating"):
input_ids = batch["input_ids"].to(device)
attention_mask = batch["attention_mask"].to(device)
labels = batch["domain"].to(device)
embeddings = model(input_ids, attention_mask)
loss = criterion(embeddings, labels)
total_loss += loss.item()
return total_loss / len(dataloader)
def main():
parser = argparse.ArgumentParser(description="Train shared encoder")
parser.add_argument("--data_dir", type=str, default="../../data", help="Data directory")
parser.add_argument("--output_dir", type=str, default="../../experts", help="Output directory")
parser.add_argument("--epochs", type=int, default=10, help="Number of epochs")
parser.add_argument("--batch_size", type=int, default=32, help="Batch size")
parser.add_argument("--lr", type=float, default=1e-4, help="Learning rate")
parser.add_argument("--samples_per_expert", type=int, default=5000, help="Samples per expert")
parser.add_argument("--max_length", type=int, default=512, help="Max sequence length")
parser.add_argument("--wandb_project", type=str, default="lego-moe", help="W&B project name")
parser.add_argument("--no_wandb", action="store_true", help="Disable W&B logging")
args = parser.parse_args()
# Setup
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
print(f"Using device: {device}")
data_dir = Path(args.data_dir)
output_dir = Path(args.output_dir)
output_dir.mkdir(parents=True, exist_ok=True)
# Initialize wandb
if not args.no_wandb:
wandb.init(
project=args.wandb_project,
name="shared-encoder-training",
config=vars(args)
)
# Load tokenizer
print("Loading tokenizer...")
tokenizer = AutoTokenizer.from_pretrained("bert-base-uncased")
# Create datasets
print("Creating datasets...")
train_dataset = MixedCorpusDataset(
data_dir,
tokenizer,
max_length=args.max_length,
samples_per_expert=args.samples_per_expert
)
# Split into train/val
train_size = int(0.95 * len(train_dataset))
val_size = len(train_dataset) - train_size
train_dataset, val_dataset = torch.utils.data.random_split(
train_dataset,
[train_size, val_size]
)
train_loader = DataLoader(
train_dataset,
batch_size=args.batch_size,
shuffle=True,
num_workers=4,
pin_memory=True
)
val_loader = DataLoader(
val_dataset,
batch_size=args.batch_size,
shuffle=False,
num_workers=4,
pin_memory=True
)
# Create model
print("Creating model...")
model = create_encoder({
"vocab_size": tokenizer.vocab_size,
"embed_dim": 256,
"num_layers": 4,
"num_heads": 8,
"ff_dim": 1024,
"dropout": 0.1,
"max_seq_len": args.max_length
})
model = model.to(device)
num_params, size_mb = model.get_model_size()
print(f"Model parameters: {num_params:,}")
print(f"Model size: {size_mb:.2f} MB")
# Create optimizer and scheduler
optimizer = AdamW(model.parameters(), lr=args.lr, weight_decay=0.01)
scheduler = CosineAnnealingLR(optimizer, T_max=args.epochs * len(train_loader))
# Create loss function
criterion = ContrastiveLoss(temperature=0.07)
# Training loop
print(f"\nStarting training for {args.epochs} epochs...")
best_val_loss = float("inf")
for epoch in range(1, args.epochs + 1):
print(f"\n{'='*60}")
print(f"Epoch {epoch}/{args.epochs}")
print(f"{'='*60}")
# Train
train_loss = train_epoch(model, train_loader, optimizer, criterion, device, epoch)
# Validate
val_loss = validate(model, val_loader, criterion, device)
# Update scheduler
scheduler.step()
print(f"Train Loss: {train_loss:.4f}")
print(f"Val Loss: {val_loss:.4f}")
# Log to wandb
if not args.no_wandb:
wandb.log({
"epoch": epoch,
"train/epoch_loss": train_loss,
"val/loss": val_loss,
"lr": optimizer.param_groups[0]["lr"]
})
# Save best model
if val_loss < best_val_loss:
best_val_loss = val_loss
checkpoint_path = output_dir / "encoder_best.pt"
torch.save({
"epoch": epoch,
"model_state_dict": model.state_dict(),
"optimizer_state_dict": optimizer.state_dict(),
"val_loss": val_loss,
"config": model.__dict__
}, checkpoint_path)
print(f"✓ Saved best model to {checkpoint_path}")
# Save checkpoint
checkpoint_path = output_dir / f"encoder_epoch_{epoch}.pt"
torch.save({
"epoch": epoch,
"model_state_dict": model.state_dict(),
"optimizer_state_dict": optimizer.state_dict(),
"val_loss": val_loss
}, checkpoint_path)
# Export final model
print("\nExporting model to ONNX...")
model.eval()
onnx_path = output_dir / "encoder.onnx"
model.export_to_onnx(str(onnx_path))
# Save tokenizer
tokenizer.save_pretrained(str(output_dir / "tokenizer"))
print("\n✅ Training complete!")
print(f"Best validation loss: {best_val_loss:.4f}")
print(f"Model saved to: {output_dir}")
print(f"\nNext steps:")
print(f" 1. Generate embeddings: python ../datasets/generate_embeddings.py")
print(f" 2. Train experts: python ../distillation/train_expert.py")
if not args.no_wandb:
wandb.finish()
if __name__ == "__main__":
main()