memoryai commited on
Commit
d79aee0
·
verified ·
1 Parent(s): 5f4163e

Upload folder using huggingface_hub

Browse files
scripts/training/run_train_flux.sh CHANGED
@@ -1,25 +1,29 @@
1
  #!/bin/bash
2
- # Launch Flux LoRA training on 2x H100
 
 
3
  # Usage: bash scripts/training/run_train_flux.sh
4
 
5
  export PYTHONPATH="/home/adminuser/chungcat:$PYTHONPATH"
6
- export TORCH_DISTRIBUTED_DEBUG=DETAIL
 
 
7
 
8
- accelerate launch \
9
- --config_file /home/adminuser/chungcat/configs/accelerate_config.yaml \
10
- /home/adminuser/chungcat/scripts/training/train_flux_lora.py \
11
  --model-name "black-forest-labs/FLUX.1-schnell" \
12
  --data-dir "/home/adminuser/chungcat/data/processed/flux_train/shards" \
13
  --output-dir "/home/adminuser/chungcat/checkpoints/flux_lora" \
14
  --resolution 1024 \
15
  --batch-size 1 \
16
- --gradient-accumulation 4 \
17
  --learning-rate 1e-4 \
18
  --lr-scheduler cosine \
19
- --lr-warmup-steps 500 \
20
  --max-train-steps 100000 \
21
  --save-steps 5000 \
22
  --lora-rank 128 \
23
  --lora-alpha 128 \
24
- --mixed-precision bf16 \
25
- --seed 42
 
 
 
1
  #!/bin/bash
2
+ # Launch Flux LoRA training - split model across 2 GPUs
3
+ # GPU 0: VAE + CLIP + T5 (encoding)
4
+ # GPU 1: Flux Transformer (training)
5
  # Usage: bash scripts/training/run_train_flux.sh
6
 
7
  export PYTHONPATH="/home/adminuser/chungcat:$PYTHONPATH"
8
+ export HF_HOME="/home/adminuser/.cache/huggingface"
9
+ export WANDB_MODE=disabled
10
+ export PYTORCH_CUDA_ALLOC_CONF=expandable_segments:True
11
 
12
+ python3 /home/adminuser/chungcat/scripts/training/train_flux_lora.py \
 
 
13
  --model-name "black-forest-labs/FLUX.1-schnell" \
14
  --data-dir "/home/adminuser/chungcat/data/processed/flux_train/shards" \
15
  --output-dir "/home/adminuser/chungcat/checkpoints/flux_lora" \
16
  --resolution 1024 \
17
  --batch-size 1 \
18
+ --gradient-accumulation 8 \
19
  --learning-rate 1e-4 \
20
  --lr-scheduler cosine \
21
+ --lr-warmup-steps 1000 \
22
  --max-train-steps 100000 \
23
  --save-steps 5000 \
24
  --lora-rank 128 \
25
  --lora-alpha 128 \
26
+ --seed 42 \
27
+ --gradient-checkpointing \
28
+ --encode-device cuda:0 \
29
+ --train-device cuda:1
scripts/training/run_train_sr_2gpu.sh ADDED
@@ -0,0 +1,82 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ #!/bin/bash
2
+ # SR Training + Auto-backup for VPS 2x H100
3
+ # This script runs on the 2-GPU VPS:
4
+ # - Stage 2: SR 1K→2K
5
+ # - Stage 3: SR 2K→4K (after Stage 2 converges)
6
+ # - Auto-backup to HuggingFace every 30 minutes
7
+ #
8
+ # Usage: bash scripts/training/run_train_sr_2gpu.sh <hf_token>
9
+
10
+ set -e
11
+
12
+ HF_TOKEN=${1:-""}
13
+ PROJECT_DIR="/home/adminuser/chungcat"
14
+
15
+ if [ -z "$HF_TOKEN" ]; then
16
+ echo "Usage: bash scripts/training/run_train_sr_2gpu.sh <hf_token>"
17
+ exit 1
18
+ fi
19
+
20
+ # Login HuggingFace
21
+ echo "=== Logging into HuggingFace ==="
22
+ python3 -c "from huggingface_hub import login; login(token='$HF_TOKEN')"
23
+ HF_USER=$(python3 -c "from huggingface_hub import HfApi; print(HfApi().whoami()['name'])")
24
+ echo "Logged in as: $HF_USER"
25
+
26
+ # Start auto-backup in background
27
+ echo "=== Starting auto-backup (every 30 min) ==="
28
+ pkill -f "backup.py --auto" 2>/dev/null || true
29
+ nohup python3 "$PROJECT_DIR/scripts/backup.py" --auto --interval 30 --user "$HF_USER" \
30
+ > "$PROJECT_DIR/logs/backup.log" 2>&1 &
31
+ echo "Auto-backup PID: $!"
32
+
33
+ # Create SR pairs if not exist
34
+ SR_PAIRS="$PROJECT_DIR/data/processed/sr_pairs"
35
+ if [ ! -d "$SR_PAIRS/1k_input" ] || [ $(ls "$SR_PAIRS/1k_input"/*.png 2>/dev/null | wc -l) -lt 100 ]; then
36
+ echo "=== Creating SR pairs from 4K images ==="
37
+ python3 "$PROJECT_DIR/scripts/data_collection/create_sr_pairs.py" \
38
+ --input-dir "$PROJECT_DIR/data/processed/sr_4k/shards" \
39
+ --output-dir "$SR_PAIRS" 2>&1 | tail -5
40
+ fi
41
+
42
+ # Train Stage 2: 1K→2K on GPU 0
43
+ echo "=== Starting SR Stage 2 (1K→2K) on GPU 0 ==="
44
+ export CUDA_VISIBLE_DEVICES=0
45
+ nohup python3 "$PROJECT_DIR/scripts/training/train_sr.py" \
46
+ --stage 2 \
47
+ --input-dir "$SR_PAIRS/1k_input" \
48
+ --target-dir "$SR_PAIRS/2k_target" \
49
+ --output-dir "$PROJECT_DIR/checkpoints/sr_stage2" \
50
+ --batch-size 4 \
51
+ --learning-rate 2e-4 \
52
+ --max-steps 200000 \
53
+ --save-steps 10000 \
54
+ --base-channels 64 \
55
+ --perceptual-weight 0.1 \
56
+ > "$PROJECT_DIR/logs/train_sr_stage2.log" 2>&1 &
57
+ echo "SR Stage 2 PID: $!"
58
+
59
+ # Train Stage 3: 2K→4K on GPU 1
60
+ echo "=== Starting SR Stage 3 (2K→4K) on GPU 1 ==="
61
+ export CUDA_VISIBLE_DEVICES=1
62
+ nohup python3 "$PROJECT_DIR/scripts/training/train_sr.py" \
63
+ --stage 3 \
64
+ --input-dir "$SR_PAIRS/2k_input" \
65
+ --target-dir "$SR_PAIRS/4k_target" \
66
+ --output-dir "$PROJECT_DIR/checkpoints/sr_stage3" \
67
+ --batch-size 2 \
68
+ --learning-rate 2e-4 \
69
+ --max-steps 200000 \
70
+ --save-steps 10000 \
71
+ --base-channels 64 \
72
+ --perceptual-weight 0.1 \
73
+ > "$PROJECT_DIR/logs/train_sr_stage3.log" 2>&1 &
74
+ echo "SR Stage 3 PID: $!"
75
+
76
+ echo ""
77
+ echo "=== All jobs started ==="
78
+ echo "Monitor:"
79
+ echo " tail -f $PROJECT_DIR/logs/train_sr_stage2.log"
80
+ echo " tail -f $PROJECT_DIR/logs/train_sr_stage3.log"
81
+ echo " tail -f $PROJECT_DIR/logs/backup.log"
82
+ echo " nvidia-smi"
scripts/training/train_flux_lora.py CHANGED
@@ -1,22 +1,16 @@
1
  """
2
  Fine-tune Flux model using LoRA on downloaded COYO dataset.
3
- Uses diffusers + accelerate + DeepSpeed for multi-GPU training.
4
  """
5
  import argparse
6
- import math
7
  from pathlib import Path
8
 
9
  import torch
10
  import webdataset as wds
11
  from PIL import Image
12
  from torchvision import transforms
13
- from diffusers import FluxPipeline, FluxTransformer2DModel
14
- from diffusers.training_utils import compute_snr
15
  from peft import LoraConfig, get_peft_model
16
- from accelerate import Accelerator
17
- from accelerate.utils import ProjectConfiguration
18
- from transformers import CLIPTextModel, CLIPTokenizer, T5EncoderModel, T5TokenizerFast
19
- import wandb
20
 
21
 
22
  def get_train_transforms(resolution=1024):
@@ -34,7 +28,7 @@ def collate_batch(samples):
34
  return {"image": images, "caption": captions}
35
 
36
 
37
- def create_webdataset(data_dir, resolution=1024, batch_size=4):
38
  transform = get_train_transforms(resolution)
39
 
40
  def preprocess(sample):
@@ -52,7 +46,7 @@ def create_webdataset(data_dir, resolution=1024, batch_size=4):
52
  raise ValueError(f"No tar files found in {data_dir}")
53
 
54
  dataset = (
55
- wds.WebDataset([str(f) for f in tar_files], shardshuffle=True, nodesplitter=wds.split_by_node)
56
  .shuffle(1000)
57
  .decode("pil")
58
  .map(preprocess)
@@ -61,6 +55,13 @@ def create_webdataset(data_dir, resolution=1024, batch_size=4):
61
  return dataset
62
 
63
 
 
 
 
 
 
 
 
64
  def main():
65
  parser = argparse.ArgumentParser(description="Fine-tune Flux with LoRA")
66
  parser.add_argument("--model-name", default="black-forest-labs/FLUX.1-schnell")
@@ -68,73 +69,83 @@ def main():
68
  parser.add_argument("--output-dir", type=Path, default=Path("/home/adminuser/chungcat/checkpoints/flux_lora"))
69
  parser.add_argument("--resolution", type=int, default=1024)
70
  parser.add_argument("--batch-size", type=int, default=1)
71
- parser.add_argument("--gradient-accumulation", type=int, default=4)
72
  parser.add_argument("--learning-rate", type=float, default=1e-4)
73
  parser.add_argument("--lr-scheduler", default="cosine")
74
- parser.add_argument("--lr-warmup-steps", type=int, default=500)
75
  parser.add_argument("--max-train-steps", type=int, default=100000)
76
  parser.add_argument("--save-steps", type=int, default=5000)
77
  parser.add_argument("--lora-rank", type=int, default=128)
78
  parser.add_argument("--lora-alpha", type=int, default=128)
79
- parser.add_argument("--mixed-precision", default="bf16")
80
  parser.add_argument("--seed", type=int, default=42)
81
- parser.add_argument("--use-wandb", action="store_true")
82
- parser.add_argument("--wandb-project", default="flux-finetune")
 
83
  args = parser.parse_args()
84
 
85
- # Setup accelerator
86
- project_config = ProjectConfiguration(
87
- project_dir=str(args.output_dir),
88
- logging_dir=str(args.output_dir / "logs"),
89
- )
90
- accelerator = Accelerator(
91
- mixed_precision=args.mixed_precision,
92
- gradient_accumulation_steps=args.gradient_accumulation,
93
- project_config=project_config,
94
- )
95
 
96
- if accelerator.is_main_process:
97
- args.output_dir.mkdir(parents=True, exist_ok=True)
98
- if args.use_wandb:
99
- wandb.init(project=args.wandb_project, config=vars(args))
100
 
101
- # Load model
102
- print(f"Loading model: {args.model_name}")
103
- pipe = FluxPipeline.from_pretrained(
104
- args.model_name,
105
- torch_dtype=torch.bfloat16,
106
- )
107
 
108
- transformer = pipe.transformer
109
- text_encoder = pipe.text_encoder
110
- text_encoder_2 = pipe.text_encoder_2
111
- tokenizer = pipe.tokenizer
112
- tokenizer_2 = pipe.tokenizer_2
113
- vae = pipe.vae
114
 
115
- # Freeze everything except transformer
 
 
116
  vae.requires_grad_(False)
 
 
 
 
117
  text_encoder.requires_grad_(False)
 
 
 
 
118
  text_encoder_2.requires_grad_(False)
119
 
120
- # Apply LoRA to transformer
 
 
 
 
 
 
 
 
 
 
 
 
121
  lora_config = LoraConfig(
122
  r=args.lora_rank,
123
  lora_alpha=args.lora_alpha,
124
- target_modules=["to_q", "to_k", "to_v", "to_out.0", "proj_in", "proj_out"],
125
- lora_dropout=0.05,
126
  )
127
  transformer = get_peft_model(transformer, lora_config)
 
128
  transformer.print_trainable_parameters()
 
129
 
130
- # Optimizer
131
  optimizer = torch.optim.AdamW(
132
- transformer.parameters(),
133
  lr=args.learning_rate,
134
  weight_decay=0.01,
135
  )
136
 
137
- # Learning rate scheduler
138
  from diffusers.optimization import get_scheduler
139
  lr_scheduler = get_scheduler(
140
  args.lr_scheduler,
@@ -143,133 +154,117 @@ def main():
143
  num_training_steps=args.max_train_steps,
144
  )
145
 
146
- # Dataset
147
  print(f"Loading dataset from {args.data_dir}")
148
  train_dataset = create_webdataset(args.data_dir, args.resolution, args.batch_size)
149
  train_dataloader = torch.utils.data.DataLoader(
150
  train_dataset, batch_size=None, num_workers=4, pin_memory=True
151
  )
152
 
153
- # Prepare with accelerator (skip dataloader — it contains strings that can't be gathered)
154
- transformer, optimizer, lr_scheduler = accelerator.prepare(
155
- transformer, optimizer, lr_scheduler
156
- )
157
-
158
- # Move frozen models to device
159
- vae.to(accelerator.device, dtype=torch.bfloat16)
160
- text_encoder.to(accelerator.device, dtype=torch.bfloat16)
161
- text_encoder_2.to(accelerator.device, dtype=torch.bfloat16)
162
-
163
- # Training loop
164
  global_step = 0
165
- print(f"Starting training for {args.max_train_steps} steps...")
 
 
 
 
166
 
167
- def pack_latents(latents):
168
- # Pack 2x2 patches: (B, C, H, W) -> (B, H//2 * W//2, C*4)
169
- b, c, h, w = latents.shape
170
- latents = latents.reshape(b, c, h // 2, 2, w // 2, 2)
171
- latents = latents.permute(0, 2, 4, 1, 3, 5).reshape(b, (h // 2) * (w // 2), c * 4)
172
- return latents
173
 
174
- transformer.train()
175
- for batch in train_dataloader:
176
- if global_step >= args.max_train_steps:
177
- break
178
 
179
- with accelerator.accumulate(transformer):
180
- images = batch["image"].to(accelerator.device, dtype=torch.bfloat16)
181
  captions = batch["caption"]
182
 
183
- # Encode images to latents
184
  with torch.no_grad():
185
  latents = vae.encode(images).latent_dist.sample()
186
- latents = (latents - vae.config.shift_factor) * vae.config.scaling_factor
187
 
188
- # Encode text: CLIP for pooled, T5 for sequence
189
- with torch.no_grad():
190
- # CLIP text encoder -> pooled embeddings
191
- text_input_ids = tokenizer(
192
  captions, padding="max_length", max_length=77,
193
  truncation=True, return_tensors="pt"
194
- ).input_ids.to(accelerator.device)
195
- pooled_prompt_embeds = text_encoder(text_input_ids, output_hidden_states=False).pooler_output
196
 
197
- # T5 text encoder -> sequence embeddings
198
- text_input_ids_2 = tokenizer_2(
199
- captions, padding="max_length", max_length=512,
200
  truncation=True, return_tensors="pt"
201
- ).input_ids.to(accelerator.device)
202
- encoder_hidden_states = text_encoder_2(text_input_ids_2)[0]
 
 
 
 
 
203
 
204
- # Flow matching: sample timesteps uniformly and interpolate
205
  noise = torch.randn_like(latents)
206
- t = torch.rand(latents.shape[0], device=latents.device, dtype=latents.dtype)
207
  t_expand = t.view(-1, 1, 1, 1)
208
-
209
- # Noisy latents via linear interpolation
210
  noisy_latents = (1 - t_expand) * latents + t_expand * noise
211
 
212
- # Pack latents into sequence format for transformer
213
- noisy_latents = pack_latents(noisy_latents)
214
- target_latents = pack_latents(noise - latents)
215
 
216
- # Flux expects timesteps scaled to [0, 1000]
217
- timesteps = (t * 1000).to(dtype=noisy_latents.dtype)
218
 
219
- # Generate image position IDs
220
- b, seq_len, _ = noisy_latents.shape
221
- img_ids = torch.zeros(seq_len, 3, device=accelerator.device, dtype=noisy_latents.dtype)
222
  h_patches = w_patches = int(seq_len ** 0.5)
223
- img_ids[:, 1] = torch.arange(h_patches, device=accelerator.device).repeat_interleave(w_patches).to(noisy_latents.dtype)
224
- img_ids[:, 2] = torch.arange(w_patches, device=accelerator.device).repeat(h_patches).to(noisy_latents.dtype)
225
- img_ids = img_ids.unsqueeze(0).expand(b, -1, -1)
226
-
227
- # Text position IDs
228
- txt_ids = torch.zeros(b, encoder_hidden_states.shape[1], 3, device=accelerator.device, dtype=noisy_latents.dtype)
229
-
230
- # Predict velocity
231
- model_pred = transformer(
232
- hidden_states=noisy_latents,
233
- timestep=timesteps / 1000,
234
- encoder_hidden_states=encoder_hidden_states,
235
- pooled_projections=pooled_prompt_embeds,
236
- img_ids=img_ids,
237
- txt_ids=txt_ids,
238
- return_dict=False,
239
- )[0]
240
-
241
- # Flow matching loss
242
- loss = torch.nn.functional.mse_loss(model_pred, target_latents, reduction="mean")
243
-
244
- accelerator.backward(loss)
245
- if accelerator.sync_gradients:
246
- accelerator.clip_grad_norm_(transformer.parameters(), 1.0)
247
- optimizer.step()
248
- lr_scheduler.step()
249
- optimizer.zero_grad()
250
-
251
- if accelerator.sync_gradients:
 
 
 
 
 
 
252
  global_step += 1
253
 
254
  if global_step % 100 == 0:
255
- if accelerator.is_main_process:
256
- print(f"Step {global_step}/{args.max_train_steps}, Loss: {loss.item():.4f}, LR: {lr_scheduler.get_last_lr()[0]:.2e}")
257
- if args.use_wandb:
258
- wandb.log({"loss": loss.item(), "lr": lr_scheduler.get_last_lr()[0], "step": global_step})
259
 
260
  if global_step % args.save_steps == 0:
261
- if accelerator.is_main_process:
262
- save_path = args.output_dir / f"checkpoint-{global_step}"
263
- accelerator.unwrap_model(transformer).save_pretrained(save_path)
264
- print(f"Saved checkpoint to {save_path}")
265
-
266
- # Save final model
267
- if accelerator.is_main_process:
268
- final_path = args.output_dir / "final"
269
- accelerator.unwrap_model(transformer).save_pretrained(final_path)
270
- print(f"Training complete! Final model saved to {final_path}")
271
- if args.use_wandb:
272
- wandb.finish()
273
 
274
 
275
  if __name__ == "__main__":
 
1
  """
2
  Fine-tune Flux model using LoRA on downloaded COYO dataset.
3
+ Split approach: VAE+text encoders on cuda:0, transformer on cuda:1.
4
  """
5
  import argparse
6
+ import gc
7
  from pathlib import Path
8
 
9
  import torch
10
  import webdataset as wds
11
  from PIL import Image
12
  from torchvision import transforms
 
 
13
  from peft import LoraConfig, get_peft_model
 
 
 
 
14
 
15
 
16
  def get_train_transforms(resolution=1024):
 
28
  return {"image": images, "caption": captions}
29
 
30
 
31
+ def create_webdataset(data_dir, resolution=1024, batch_size=1):
32
  transform = get_train_transforms(resolution)
33
 
34
  def preprocess(sample):
 
46
  raise ValueError(f"No tar files found in {data_dir}")
47
 
48
  dataset = (
49
+ wds.WebDataset([str(f) for f in tar_files], shardshuffle=True)
50
  .shuffle(1000)
51
  .decode("pil")
52
  .map(preprocess)
 
55
  return dataset
56
 
57
 
58
+ def pack_latents(latents):
59
+ b, c, h, w = latents.shape
60
+ latents = latents.reshape(b, c, h // 2, 2, w // 2, 2)
61
+ latents = latents.permute(0, 2, 4, 1, 3, 5).reshape(b, (h // 2) * (w // 2), c * 4)
62
+ return latents
63
+
64
+
65
  def main():
66
  parser = argparse.ArgumentParser(description="Fine-tune Flux with LoRA")
67
  parser.add_argument("--model-name", default="black-forest-labs/FLUX.1-schnell")
 
69
  parser.add_argument("--output-dir", type=Path, default=Path("/home/adminuser/chungcat/checkpoints/flux_lora"))
70
  parser.add_argument("--resolution", type=int, default=1024)
71
  parser.add_argument("--batch-size", type=int, default=1)
72
+ parser.add_argument("--gradient-accumulation", type=int, default=8)
73
  parser.add_argument("--learning-rate", type=float, default=1e-4)
74
  parser.add_argument("--lr-scheduler", default="cosine")
75
+ parser.add_argument("--lr-warmup-steps", type=int, default=1000)
76
  parser.add_argument("--max-train-steps", type=int, default=100000)
77
  parser.add_argument("--save-steps", type=int, default=5000)
78
  parser.add_argument("--lora-rank", type=int, default=128)
79
  parser.add_argument("--lora-alpha", type=int, default=128)
 
80
  parser.add_argument("--seed", type=int, default=42)
81
+ parser.add_argument("--gradient-checkpointing", action="store_true", default=True)
82
+ parser.add_argument("--encode-device", default="cuda:0")
83
+ parser.add_argument("--train-device", default="cuda:1")
84
  args = parser.parse_args()
85
 
86
+ args.output_dir.mkdir(parents=True, exist_ok=True)
87
+ torch.manual_seed(args.seed)
 
 
 
 
 
 
 
 
88
 
89
+ encode_device = torch.device(args.encode_device)
90
+ train_device = torch.device(args.train_device)
 
 
91
 
92
+ # --- Load tokenizers ---
93
+ print("Loading tokenizers...")
94
+ from transformers import CLIPTokenizer, T5TokenizerFast
95
+ tokenizer = CLIPTokenizer.from_pretrained(args.model_name, subfolder="tokenizer")
96
+ tokenizer_2 = T5TokenizerFast.from_pretrained(args.model_name, subfolder="tokenizer_2")
 
97
 
98
+ # --- Load VAE + text encoders on encode_device ---
99
+ print(f"Loading VAE + text encoders on {encode_device}...")
100
+ from diffusers import AutoencoderKL
101
+ from transformers import CLIPTextModel, T5EncoderModel
 
 
102
 
103
+ vae = AutoencoderKL.from_pretrained(
104
+ args.model_name, subfolder="vae", torch_dtype=torch.bfloat16
105
+ ).to(encode_device).eval()
106
  vae.requires_grad_(False)
107
+
108
+ text_encoder = CLIPTextModel.from_pretrained(
109
+ args.model_name, subfolder="text_encoder", torch_dtype=torch.bfloat16
110
+ ).to(encode_device).eval()
111
  text_encoder.requires_grad_(False)
112
+
113
+ text_encoder_2 = T5EncoderModel.from_pretrained(
114
+ args.model_name, subfolder="text_encoder_2", torch_dtype=torch.bfloat16
115
+ ).to(encode_device).eval()
116
  text_encoder_2.requires_grad_(False)
117
 
118
+ vae_shift = vae.config.shift_factor
119
+ vae_scale = vae.config.scaling_factor
120
+
121
+ # --- Load transformer on train_device ---
122
+ print(f"Loading Flux transformer on {train_device}...")
123
+ from diffusers import FluxTransformer2DModel
124
+ transformer = FluxTransformer2DModel.from_pretrained(
125
+ args.model_name, subfolder="transformer", torch_dtype=torch.bfloat16
126
+ )
127
+
128
+ if args.gradient_checkpointing:
129
+ transformer.enable_gradient_checkpointing()
130
+
131
  lora_config = LoraConfig(
132
  r=args.lora_rank,
133
  lora_alpha=args.lora_alpha,
134
+ target_modules=["to_q", "to_k", "to_v", "to_out.0"],
135
+ lora_dropout=0.0,
136
  )
137
  transformer = get_peft_model(transformer, lora_config)
138
+ transformer.to(train_device)
139
  transformer.print_trainable_parameters()
140
+ transformer.train()
141
 
142
+ # --- Optimizer + scheduler ---
143
  optimizer = torch.optim.AdamW(
144
+ [p for p in transformer.parameters() if p.requires_grad],
145
  lr=args.learning_rate,
146
  weight_decay=0.01,
147
  )
148
 
 
149
  from diffusers.optimization import get_scheduler
150
  lr_scheduler = get_scheduler(
151
  args.lr_scheduler,
 
154
  num_training_steps=args.max_train_steps,
155
  )
156
 
157
+ # --- Dataset ---
158
  print(f"Loading dataset from {args.data_dir}")
159
  train_dataset = create_webdataset(args.data_dir, args.resolution, args.batch_size)
160
  train_dataloader = torch.utils.data.DataLoader(
161
  train_dataset, batch_size=None, num_workers=4, pin_memory=True
162
  )
163
 
164
+ # --- Training loop ---
 
 
 
 
 
 
 
 
 
 
165
  global_step = 0
166
+ accum_loss = 0.0
167
+ print(f"\nStarting training for {args.max_train_steps} steps...")
168
+ print(f" Batch size: {args.batch_size}, Grad accum: {args.gradient_accumulation}")
169
+ print(f" Effective batch: {args.batch_size * args.gradient_accumulation}")
170
+ print(f" Encode device: {encode_device}, Train device: {train_device}")
171
 
172
+ scaler = None # bf16 doesn't need GradScaler
 
 
 
 
 
173
 
174
+ while global_step < args.max_train_steps:
175
+ for batch in train_dataloader:
176
+ if global_step >= args.max_train_steps:
177
+ break
178
 
179
+ images = batch["image"].to(encode_device, dtype=torch.bfloat16)
 
180
  captions = batch["caption"]
181
 
182
+ # Encode on encode_device
183
  with torch.no_grad():
184
  latents = vae.encode(images).latent_dist.sample()
185
+ latents = (latents - vae_shift) * vae_scale
186
 
187
+ text_ids = tokenizer(
 
 
 
188
  captions, padding="max_length", max_length=77,
189
  truncation=True, return_tensors="pt"
190
+ ).input_ids.to(encode_device)
191
+ pooled_prompt_embeds = text_encoder(text_ids, output_hidden_states=False).pooler_output
192
 
193
+ text_ids_2 = tokenizer_2(
194
+ captions, padding="max_length", max_length=256,
 
195
  truncation=True, return_tensors="pt"
196
+ ).input_ids.to(encode_device)
197
+ encoder_hidden_states = text_encoder_2(text_ids_2)[0]
198
+
199
+ # Move to train device
200
+ latents = latents.to(train_device)
201
+ pooled_prompt_embeds = pooled_prompt_embeds.to(train_device)
202
+ encoder_hidden_states = encoder_hidden_states.to(train_device)
203
 
204
+ # Flow matching
205
  noise = torch.randn_like(latents)
206
+ t = torch.rand(latents.shape[0], device=train_device, dtype=torch.bfloat16)
207
  t_expand = t.view(-1, 1, 1, 1)
 
 
208
  noisy_latents = (1 - t_expand) * latents + t_expand * noise
209
 
210
+ noisy_packed = pack_latents(noisy_latents)
211
+ target = pack_latents(noise - latents)
 
212
 
213
+ timesteps = (t * 1000).to(dtype=torch.bfloat16)
 
214
 
215
+ b, seq_len, _ = noisy_packed.shape
 
 
216
  h_patches = w_patches = int(seq_len ** 0.5)
217
+ img_ids = torch.zeros(b, seq_len, 3, device=train_device, dtype=torch.bfloat16)
218
+ img_ids[:, :, 1] = torch.arange(h_patches, device=train_device).repeat_interleave(w_patches).unsqueeze(0).expand(b, -1).to(torch.bfloat16)
219
+ img_ids[:, :, 2] = torch.arange(w_patches, device=train_device).repeat(h_patches).unsqueeze(0).expand(b, -1).to(torch.bfloat16)
220
+
221
+ txt_ids = torch.zeros(b, encoder_hidden_states.shape[1], 3, device=train_device, dtype=torch.bfloat16)
222
+
223
+ # Forward
224
+ with torch.amp.autocast("cuda", dtype=torch.bfloat16):
225
+ model_pred = transformer(
226
+ hidden_states=noisy_packed,
227
+ timestep=timesteps / 1000,
228
+ encoder_hidden_states=encoder_hidden_states,
229
+ pooled_projections=pooled_prompt_embeds,
230
+ img_ids=img_ids,
231
+ txt_ids=txt_ids,
232
+ return_dict=False,
233
+ )[0]
234
+
235
+ loss = torch.nn.functional.mse_loss(model_pred, target, reduction="mean")
236
+ loss = loss / args.gradient_accumulation
237
+
238
+ loss.backward()
239
+ accum_loss += loss.item()
240
+
241
+ if (global_step + 1) % args.gradient_accumulation == 0 or True:
242
+ # Check if we should step
243
+ step_count = (global_step + 1) % args.gradient_accumulation
244
+ if step_count == 0:
245
+ torch.nn.utils.clip_grad_norm_(
246
+ [p for p in transformer.parameters() if p.requires_grad], 1.0
247
+ )
248
+ optimizer.step()
249
+ lr_scheduler.step()
250
+ optimizer.zero_grad()
251
+
252
  global_step += 1
253
 
254
  if global_step % 100 == 0:
255
+ avg_loss = accum_loss / 100 * args.gradient_accumulation
256
+ print(f"Step {global_step}/{args.max_train_steps}, Loss: {avg_loss:.4f}, LR: {lr_scheduler.get_last_lr()[0]:.2e}")
257
+ accum_loss = 0.0
 
258
 
259
  if global_step % args.save_steps == 0:
260
+ save_path = args.output_dir / f"checkpoint-{global_step}"
261
+ transformer.save_pretrained(save_path)
262
+ print(f"Saved checkpoint to {save_path}")
263
+
264
+ # Save final
265
+ final_path = args.output_dir / "final"
266
+ transformer.save_pretrained(final_path)
267
+ print(f"Training complete! Final model saved to {final_path}")
 
 
 
 
268
 
269
 
270
  if __name__ == "__main__":