FIXED

train-Copy1.py

@@ -0,0 +1,679 @@
+import os
+import math
+import torch
+import numpy as np
+import matplotlib.pyplot as plt
+from torch.utils.data import DataLoader, Sampler
+from torch.utils.data.distributed import DistributedSampler
+from torch.optim.lr_scheduler import LambdaLR
+from collections import defaultdict
+from torch.optim.lr_scheduler import LambdaLR
+from diffusers import UNet2DConditionModel, AutoencoderKLWan,AutoencoderKL
+from accelerate import Accelerator
+from datasets import load_from_disk
+from tqdm import tqdm
+from PIL import Image,ImageOps
+import wandb
+import random
+import gc
+from accelerate.state import DistributedType
+from torch.distributed import broadcast_object_list
+from torch.utils.checkpoint import checkpoint
+from diffusers.models.attention_processor import AttnProcessor2_0
+from datetime import datetime
+import bitsandbytes as bnb
+import torch.nn.functional as F
+from collections import deque
+
+# --------------------------- Параметры ---------------------------
+ds_path = "/workspace/sdxs3d/datasets/mjnj"
+project = "unet"
+batch_size = 128
+base_learning_rate = 9e-5
+min_learning_rate = 1e-5
+num_epochs = 84
+# samples/save per epoch
+sample_interval_share = 5
+use_wandb = True
+use_comet_ml = False
+save_model = True
+use_decay = True
+fbp = False # fused backward pass
+optimizer_type = "adam8bit"
+torch_compile = False
+unet_gradient = True
+clip_sample = False #Scheduler
+fixed_seed = True
+shuffle = True
+comet_ml_api_key = "Agctp26mbqnoYrrlvQuKSTk6r"  # Добавлен API ключ для Comet ML
+comet_ml_workspace = "recoilme"  # Добавлен workspace для Comet ML
+torch.backends.cuda.matmul.allow_tf32 = True
+torch.backends.cudnn.allow_tf32 = True
+torch.backends.cuda.enable_mem_efficient_sdp(False)
+dtype = torch.float32
+save_barrier = 1.01
+warmup_percent = 0.01
+percentile_clipping = 99 # 8bit optim
+betta2 = 0.995
+eps = 1e-8
+clip_grad_norm = 1.0
+steps_offset = 0 # Scheduler
+limit = 0
+checkpoints_folder = ""
+mixed_precision = "no" #"fp16"
+gradient_accumulation_steps = 1
+accelerator = Accelerator(
+    mixed_precision=mixed_precision,
+    gradient_accumulation_steps=gradient_accumulation_steps
+)
+device = accelerator.device
+
+# Параметры для диффузии
+n_diffusion_steps = 50
+samples_to_generate = 12
+guidance_scale = 1
+
+# Папки для сохранения результатов
+generated_folder = "samples"
+os.makedirs(generated_folder, exist_ok=True)
+
+# Настройка seed для воспроизводимости
+current_date = datetime.now()
+seed = int(current_date.strftime("%Y%m%d"))
+if fixed_seed:
+    torch.manual_seed(seed)
+    np.random.seed(seed)
+    random.seed(seed)
+    if torch.cuda.is_available():
+        torch.cuda.manual_seed_all(seed)
+
+# --------------------------- Параметры LoRA ---------------------------
+lora_name = "" 
+lora_rank = 32
+lora_alpha = 64
+
+print("init")
+
+# ---------------------------  вспомогательные функции ---------------------------
+def sample_timesteps_bias(
+    batch_size: int,
+    progress: float,           # [0..1]
+    num_train_timesteps: int,  # обычно 1000
+    steps_offset: int = 0,
+    device=None,
+    mode: str = "beta",        # "beta", "uniform"
+) -> torch.Tensor:
+    """
+    Возвращает timesteps с разным bias:
+    - beta   : как раньше (сдвиг в начало или конец в зависимости от progress)
+    - normal : около середины (гауссовое распределение)
+    - uniform: равномерно по всем timestep’ам
+    """
+
+    max_idx = num_train_timesteps - 1 - steps_offset
+
+    if mode == "beta":
+        alpha = 1.0 + .5 * (1.0 - progress)
+        beta  = 1.0 + .5 * progress
+        samples = torch.distributions.Beta(alpha, beta).sample((batch_size,))
+
+    elif mode == "uniform":
+        samples = torch.rand(batch_size)
+
+    else:
+        raise ValueError(f"Unknown mode: {mode}")
+
+    timesteps = steps_offset + (samples * max_idx).long().to(device)
+    return timesteps
+
+def logit_normal_samples(shape, mu=0.0, sigma=1.0, device=None, dtype=None):
+    normal_samples = torch.normal(mean=mu, std=sigma, size=shape, device=device, dtype=dtype)
+
+    logit_normal_samples = torch.sigmoid(normal_samples)
+
+    return logit_normal_samples
+
+# --------------------------- Инициализация WandB ---------------------------
+if accelerator.is_main_process:
+    if use_wandb:
+        wandb.init(project=project+lora_name, config={
+            "batch_size": batch_size,
+            "base_learning_rate": base_learning_rate,
+            "num_epochs": num_epochs,
+            "fbp": fbp,
+            "optimizer_type": optimizer_type,
+        })
+    if use_comet_ml:
+        from comet_ml import Experiment
+        comet_experiment = Experiment(
+            api_key=comet_ml_api_key,
+            project_name=project,
+            workspace=comet_ml_workspace
+        )
+        # Логируем гиперпараметры в Comet ML
+        hyper_params = {
+            "batch_size": batch_size,
+            "base_learning_rate": base_learning_rate,
+            "min_learning_rate": min_learning_rate,
+            "num_epochs": num_epochs,
+            "n_diffusion_steps": n_diffusion_steps,
+            "guidance_scale": guidance_scale,
+            "optimizer_type": optimizer_type,
+            "mixed_precision": mixed_precision,
+        }
+        comet_experiment.log_parameters(hyper_params)
+
+# Включение Flash Attention 2/SDPA
+torch.backends.cuda.enable_flash_sdp(True)
+# --------------------------- Инициализация Accelerator --------------------
+gen = torch.Generator(device=device)
+gen.manual_seed(seed)
+
+# --------------------------- Загрузка моделей ---------------------------
+# VAE загружается на CPU для экономии GPU-памяти (как в твоём оригинальном коде)
+vae = AutoencoderKL.from_pretrained("AiArtLab/simplevae",subfolder="simple_vae_nightly",torch_dtype=dtype).to("cpu").eval()
+
+shift_factor = getattr(vae.config, "shift_factor", 0.0)
+if shift_factor is None:
+    shift_factor = 0.0
+
+scaling_factor = getattr(vae.config, "scaling_factor", 1.0)
+if scaling_factor is None:
+    scaling_factor = 1.0
+    
+latents_mean = getattr(vae.config, "latents_mean", None)
+latents_std = getattr(vae.config, "latents_std", None)
+
+
+
+
+class DistributedResolutionBatchSampler(Sampler):
+    def __init__(self, dataset, batch_size, num_replicas, rank, shuffle=True, drop_last=True):
+        self.dataset = dataset
+        self.batch_size = max(1, batch_size // num_replicas)
+        self.num_replicas = num_replicas
+        self.rank = rank
+        self.shuffle = shuffle
+        self.drop_last = drop_last
+        self.epoch = 0
+        
+        try:
+            widths = np.array(dataset["width"])
+            heights = np.array(dataset["height"])
+        except KeyError:
+            widths = np.zeros(len(dataset))
+            heights = np.zeros(len(dataset))
+        
+        self.size_keys = np.unique(np.stack([widths, heights], axis=1), axis=0)
+        self.size_groups = {}
+        for w, h in self.size_keys:
+            mask = (widths == w) & (heights == h)
+            self.size_groups[(w, h)] = np.where(mask)[0]
+            
+        self.group_num_batches = {}
+        total_batches = 0
+        for size, indices in self.size_groups.items():
+            num_full_batches = len(indices) // (self.batch_size * self.num_replicas)
+            self.group_num_batches[size] = num_full_batches
+            total_batches += num_full_batches
+            
+        self.num_batches = (total_batches // self.num_replicas) * self.num_replicas
+        
+    def __iter__(self):
+        if torch.cuda.is_available():
+            torch.cuda.empty_cache()
+        all_batches = []
+        rng = np.random.RandomState(self.epoch)
+        
+        for size, indices in self.size_groups.items():
+            indices = indices.copy()
+            if self.shuffle:
+                rng.shuffle(indices)
+            num_full_batches = self.group_num_batches[size]
+            if num_full_batches == 0:
+                continue
+            valid_indices = indices[:num_full_batches * self.batch_size * self.num_replicas]
+            batches = valid_indices.reshape(-1, self.batch_size * self.num_replicas)
+            start_idx = self.rank * self.batch_size
+            end_idx = start_idx + self.batch_size
+            gpu_batches = batches[:, start_idx:end_idx]
+            all_batches.extend(gpu_batches)
+        
+        if self.shuffle:
+            rng.shuffle(all_batches)
+        accelerator.wait_for_everyone()
+        return iter(all_batches)
+
+    def __len__(self):
+        return self.num_batches 
+
+    def set_epoch(self, epoch):
+        self.epoch = epoch
+
+# Функция для выборки фиксированных семплов по размерам
+def get_fixed_samples_by_resolution(dataset, samples_per_group=1):
+    size_groups = defaultdict(list)
+    try:
+        widths = dataset["width"]
+        heights = dataset["height"]
+    except KeyError:
+        widths = [0] * len(dataset)
+        heights = [0] * len(dataset)
+    for i, (w, h) in enumerate(zip(widths, heights)):
+        size = (w, h)
+        size_groups[size].append(i)
+    
+    fixed_samples = {}
+    for size, indices in size_groups.items():
+        n_samples = min(samples_per_group, len(indices))
+        if len(size_groups)==1:
+            n_samples = samples_to_generate
+        if n_samples == 0:
+            continue
+        sample_indices = random.sample(indices, n_samples)
+        samples_data = [dataset[idx] for idx in sample_indices]
+        latents = torch.tensor(np.array([item["vae"] for item in samples_data])).to(device=device,dtype=dtype)
+        embeddings = torch.tensor(np.array([item["embeddings"] for item in samples_data])).to(device,dtype=dtype)
+        texts = [item["text"] for item in samples_data]
+        fixed_samples[size] = (latents, embeddings, texts)
+    
+    print(f"Создано {len(fixed_samples)} групп фиксированных семплов по разрешениям")
+    return fixed_samples
+
+if limit > 0:
+    dataset = load_from_disk(ds_path).select(range(limit))
+else:
+    dataset = load_from_disk(ds_path)
+
+def collate_fn_simple(batch):
+    latents = torch.tensor(np.array([item["vae"] for item in batch])).to(device,dtype=dtype)
+    embeddings = torch.tensor(np.array([item["embeddings"] for item in batch])).to(device,dtype=dtype)
+    return latents, embeddings
+
+batch_sampler = DistributedResolutionBatchSampler(
+        dataset=dataset,
+        batch_size=batch_size,
+        num_replicas=accelerator.num_processes,
+        rank=accelerator.process_index,
+        shuffle=shuffle
+    )
+
+dataloader = DataLoader(dataset, batch_sampler=batch_sampler, collate_fn=collate_fn_simple)
+print("Total samples",len(dataloader))
+dataloader = accelerator.prepare(dataloader)
+
+start_epoch = 0
+global_step = 0
+total_training_steps = (len(dataloader) * num_epochs)
+world_size = accelerator.state.num_processes
+
+# Опция загрузки модели из последнего чекпоинта (если существует)
+latest_checkpoint = os.path.join(checkpoints_folder, project)
+if os.path.isdir(latest_checkpoint):
+    print("Загружаем UNet из чекпоинта:", latest_checkpoint)
+    unet = UNet2DConditionModel.from_pretrained(latest_checkpoint).to(device=device,dtype=dtype)
+    if torch_compile:
+        print("compiling")
+        torch.set_float32_matmul_precision('high')
+        unet = torch.compile(unet)
+        print("compiling - ok")
+    if unet_gradient:
+        unet.enable_gradient_checkpointing()
+    unet.set_use_memory_efficient_attention_xformers(False)
+    try:
+        unet.set_attn_processor(AttnProcessor2_0())
+    except Exception as e:
+        print(f"Ошибка при включении SDPA: {e}")
+        unet.set_use_memory_efficient_attention_xformers(True)
+
+else:
+    # FIX: если чекпоинта нет — прекращаем с понятной ошибкой (лучше, чем неожиданные NameError дальше)
+    raise FileNotFoundError(f"UNet checkpoint not found at {latest_checkpoint}. Положи UNet чекпоинт в {latest_checkpoint} или укажи другой путь.")
+
+if lora_name:
+    print(f"--- Настройка LoRA через PEFT (Rank={lora_rank}, Alpha={lora_alpha}) ---")
+    from peft import LoraConfig, get_peft_model, prepare_model_for_kbit_training
+    from peft.tuners.lora import LoraModel
+    import os
+    unet.requires_grad_(False)
+    print("Параметры базового UNet заморожены.")
+
+    lora_config = LoraConfig(
+        r=lora_rank,
+        lora_alpha=lora_alpha,
+        target_modules=["to_q", "to_k", "to_v", "to_out.0"],
+    )
+    unet.add_adapter(lora_config)
+
+    from peft import get_peft_model
+    peft_unet = get_peft_model(unet, lora_config)
+    params_to_optimize = list(p for p in peft_unet.parameters() if p.requires_grad)
+
+    if accelerator.is_main_process:
+        lora_params_count = sum(p.numel() for p in params_to_optimize)
+        total_params_count = sum(p.numel() for p in unet.parameters())
+        print(f"Количество обучаемых параметров (LoRA): {lora_params_count:,}")
+        print(f"Общее количество параметров UNet: {total_params_count:,}")
+
+    lora_save_path = os.path.join("lora", lora_name)
+    os.makedirs(lora_save_path, exist_ok=True)
+
+    def save_lora_checkpoint(model):
+        if accelerator.is_main_process:
+            print(f"Сохраняем LoRA адаптеры  в {lora_save_path}")
+            from peft.utils.save_and_load import get_peft_model_state_dict
+            lora_state_dict = get_peft_model_state_dict(model)
+            torch.save(lora_state_dict, os.path.join(lora_save_path, "adapter_model.bin"))
+            model.peft_config["default"].save_pretrained(lora_save_path)
+            from diffusers import StableDiffusionXLPipeline
+            StableDiffusionXLPipeline.save_lora_weights(lora_save_path, lora_state_dict)
+
+# --------------------------- Оптимизатор ---------------------------
+if lora_name:
+    trainable_params = [p for p in unet.parameters() if p.requires_grad]
+else:
+    if fbp:
+        trainable_params = list(unet.parameters())
+
+def create_optimizer(name, params):
+    if name == "adam8bit":
+        return bnb.optim.AdamW8bit(
+            params, lr=base_learning_rate, betas=(0.9, betta2), eps=eps, weight_decay=0.01,
+            percentile_clipping=percentile_clipping
+        )
+    elif name == "adam":
+        return torch.optim.AdamW(
+            params, lr=base_learning_rate, betas=(0.9, 0.999), eps=1e-8, weight_decay=0.01
+        )
+    elif name == "lion8bit":
+        return bnb.optim.Lion8bit(
+            params, lr=base_learning_rate, betas=(0.9, 0.97), weight_decay=0.01,
+            percentile_clipping=percentile_clipping
+        )
+    elif name == "adafactor":
+        from transformers import Adafactor
+        return Adafactor(
+            params, lr=base_learning_rate, scale_parameter=True, relative_step=False,
+            warmup_init=False, eps=(1e-30, 1e-3), clip_threshold=1.0,
+            beta1=0.9, weight_decay=0.01
+        )
+    else:
+        raise ValueError(f"Unknown optimizer: {name}")
+
+if fbp:
+    optimizer_dict = {p: create_optimizer(optimizer_type, [p]) for p in trainable_params}
+    def optimizer_hook(param):
+        optimizer_dict[param].step()
+        optimizer_dict[param].zero_grad(set_to_none=True)
+    for param in trainable_params:
+        param.register_post_accumulate_grad_hook(optimizer_hook)
+    unet, optimizer = accelerator.prepare(unet, optimizer_dict)
+else:
+    optimizer = create_optimizer(optimizer_type, unet.parameters())
+    def lr_schedule(step):
+        x = step / (total_training_steps * world_size)
+        warmup = warmup_percent
+        if not use_decay:
+            return base_learning_rate
+        if x < warmup:
+            return min_learning_rate + (base_learning_rate - min_learning_rate) * (x / warmup)
+        decay_ratio = (x - warmup) / (1 - warmup)
+        return min_learning_rate + 0.5 * (base_learning_rate - min_learning_rate) * \
+               (1 + math.cos(math.pi * decay_ratio))
+    lr_scheduler = LambdaLR(optimizer, lambda step: lr_schedule(step) / base_learning_rate)
+
+    num_params = sum(p.numel() for p in unet.parameters())
+    print(f"[rank {accelerator.process_index}] total params: {num_params}")
+    for name, param in unet.named_parameters():
+        if torch.isnan(param).any() or torch.isinf(param).any():
+            print(f"[rank {accelerator.process_index}] NaN/Inf in {name}")
+    unet, optimizer, lr_scheduler = accelerator.prepare(unet, optimizer, lr_scheduler)
+
+# --------------------------- Фиксированные семплы для генерации ---------------------------
+fixed_samples = get_fixed_samples_by_resolution(dataset)
+
+@torch.compiler.disable()
+@torch.no_grad()
+def generate_and_save_samples(fixed_samples_cpu, step):
+    original_model = None
+    try:
+        original_model = accelerator.unwrap_model(unet, keep_torch_compile=True).eval()
+        vae.to(device=device).eval()  # временно подгружаем VAE на GPU для декодинга
+
+        
+        all_generated_images = []
+        all_captions = [] 
+        
+        for size, (sample_latents, sample_text_embeddings, sample_text) in fixed_samples_cpu.items():
+            width, height = size
+            sample_latents = sample_latents.to(dtype=dtype, device=device)
+            sample_text_embeddings = sample_text_embeddings.to(dtype=dtype, device=device)
+
+            noise = torch.randn(
+                sample_latents.shape,
+                generator=gen,
+                device=device,
+                dtype=sample_latents.dtype
+            )
+            current_latents = noise.clone()
+            
+            if guidance_scale != 1:
+                empty_embeddings = torch.zeros_like(sample_text_embeddings, dtype=sample_text_embeddings.dtype, device=device)
+                text_embeddings_batch = torch.cat([empty_embeddings, sample_text_embeddings], dim=0)
+            else:
+                text_embeddings_batch = sample_text_embeddings
+            
+            timesteps = torch.linspace(0, 1, n_diffusion_steps+1, device=device, dtype=sample_latents.dtype)
+            for i in range(0, n_diffusion_steps):
+                t_cur = timesteps[i].unsqueeze(0)
+                t_next = timesteps[i+1]
+                dt = t_next - t_cur
+                if guidance_scale != 1:
+                    latent_model_input = torch.cat((current_latents, current_latents))
+                else:
+                    latent_model_input = current_latents
+                t_batch = t_cur.repeat(latent_model_input.shape[0]).to(device)
+                t_batch = (t_batch * 1000).long().view(-1)
+                flow = original_model(latent_model_input, t_batch, text_embeddings_batch).sample               
+                
+                if guidance_scale != 1:
+                    flow_uncond, flow_cond = flow.chunk(2)
+                    flow = flow_uncond + guidance_scale * (flow_cond - flow_uncond)
+
+                current_latents = current_latents + flow * dt.to(device)
+
+            # Параметры нормализации
+            latent_for_vae = current_latents.detach() / scaling_factor + shift_factor
+            
+            decoded = vae.decode(latent_for_vae.to(torch.float32)).sample
+            #decoded = decoded[:, :, 0, :, :]  # [3, H, W]
+            #print(decoded.ndim, decoded.shape)
+            
+            decoded_fp32 = decoded.to(torch.float32)
+            for img_idx, img_tensor in enumerate(decoded_fp32):
+
+                # Форма: [3, H, W] -> преобразуем в [H, W, 3]
+                img = (img_tensor / 2 + 0.5).clamp(0, 1).cpu().numpy()
+                img = img.transpose(1, 2, 0)  # Из [3, H, W] в [H, W, 3]
+    
+                #img = (img_tensor / 2 + 0.5).clamp(0, 1).cpu().numpy().transpose(1, 2, 0)
+                if np.isnan(img).any():
+                    print("NaNs found, saving stopped! Step:", step)
+                pil_img = Image.fromarray((img * 255).astype("uint8"))
+                
+                max_w_overall = max(s[0] for s in fixed_samples_cpu.keys())
+                max_h_overall = max(s[1] for s in fixed_samples_cpu.keys())
+                max_w_overall = max(255, max_w_overall)
+                max_h_overall = max(255, max_h_overall)
+            
+                padded_img = ImageOps.pad(pil_img, (max_w_overall, max_h_overall), color='white')
+                all_generated_images.append(padded_img)
+
+                caption_text = sample_text[img_idx][:200] if img_idx < len(sample_text) else ""
+                all_captions.append(caption_text)
+                
+                sample_path = f"{generated_folder}/{project}_{width}x{height}_{img_idx}.jpg"
+                pil_img.save(sample_path, "JPEG", quality=96)
+        
+        if use_wandb and accelerator.is_main_process:
+            wandb_images = [
+                wandb.Image(img, caption=f"{all_captions[i]}")
+                for i, img in enumerate(all_generated_images)
+            ]
+            wandb.log({"generated_images": wandb_images})
+        if use_comet_ml and accelerator.is_main_process:
+            for i, img in enumerate(all_generated_images):
+                comet_experiment.log_image(
+                    image_data=img,
+                    name=f"step_{step}_img_{i}",
+                    step=step,
+                    metadata={
+                        "caption": all_captions[i],
+                        "width": img.width,
+                        "height": img.height,
+                        "global_step": step
+                    }
+                )
+    finally:
+        # вернуть VAE на CPU (как было в твоём коде)
+        vae.to("cpu")
+        for var in list(locals().keys()):
+            if isinstance(locals()[var], torch.Tensor):
+                del locals()[var]
+        torch.cuda.empty_cache()
+        gc.collect()
+
+# --------------------------- Генерация сэмплов перед обучением ---------------------------
+if accelerator.is_main_process:
+    if save_model:
+        print("Генерация сэмплов до старта обучения...")
+        generate_and_save_samples(fixed_samples,0)
+accelerator.wait_for_everyone()
+
+# Модифицируем функцию сохранения модели для поддержки LoRA
+def save_checkpoint(unet,variant=""):
+    if accelerator.is_main_process:
+        if lora_name:
+            save_lora_checkpoint(unet)
+        else:
+            if variant!="":
+                accelerator.unwrap_model(unet.to(dtype=torch.float16)).save_pretrained(os.path.join(checkpoints_folder, f"{project}"),variant=variant)
+            else:
+                accelerator.unwrap_model(unet).save_pretrained(os.path.join(checkpoints_folder, f"{project}"))
+            unet = unet.to(dtype=dtype)
+
+# --------------------------- Тренировочный цикл ---------------------------
+if accelerator.is_main_process:
+    print(f"Total steps per GPU: {total_training_steps}")
+
+epoch_loss_points = []
+progress_bar = tqdm(total=total_training_steps, disable=not accelerator.is_local_main_process, desc="Training", unit="step")
+
+steps_per_epoch = len(dataloader)
+sample_interval = max(1, steps_per_epoch // sample_interval_share)
+min_loss = 2.
+
+for epoch in range(start_epoch, start_epoch + num_epochs):
+    batch_losses = []
+    batch_grads = []
+    batch_sampler.set_epoch(epoch)
+    accelerator.wait_for_everyone()
+    unet.train()
+    #print("epoch:",epoch)
+    for step, (latents, embeddings) in enumerate(dataloader):
+        with accelerator.accumulate(unet):
+            if save_model == False and step == 5 :
+                used_gb = torch.cuda.max_memory_allocated() / 1024**3
+                print(f"Шаг {step}: {used_gb:.2f} GB")
+                
+            noise = torch.randn_like(latents, dtype=latents.dtype)
+            t = logit_normal_samples((latents.shape[0], 1, 1, 1), mu=0.0, sigma=1.0, device=latents.device, dtype=latents.dtype)
+            noisy_latents = (1 - t) * noise + t * latents
+
+            t_for_unet = (t * 1000).long().view(-1)
+            model_pred = unet(noisy_latents, t_for_unet, embeddings).sample
+            target_pred = latents - noise
+
+            mse_loss = F.mse_loss(model_pred.float(), target_pred.float())
+
+            # Сохраняем для логов (мы сохраняем MSE отдельно — как показатель)
+            batch_losses.append(mse_loss.detach().item())
+
+            if (global_step % 100 == 0) or (global_step % sample_interval == 0):
+                accelerator.wait_for_everyone()
+                
+            # Backward
+            accelerator.backward(mse_loss)
+
+            if (global_step % 100 == 0) or (global_step % sample_interval == 0):
+                accelerator.wait_for_everyone()
+                
+            grad = 0.0
+            if not fbp:
+                if accelerator.sync_gradients:
+                    with torch.amp.autocast('cuda', enabled=False):
+                        grad_val = accelerator.clip_grad_norm_(unet.parameters(), clip_grad_norm)
+                    grad = float(grad_val)
+                    optimizer.step()
+                    lr_scheduler.step()
+                    optimizer.zero_grad(set_to_none=True)
+
+            global_step += 1
+            progress_bar.update(1)
+
+            # Логируем метрики
+            if accelerator.is_main_process:
+                if fbp:
+                    current_lr = base_learning_rate
+                else:
+                    current_lr = lr_scheduler.get_last_lr()[0]
+                batch_grads.append(grad)
+
+                log_data = {}
+                log_data["loss"] = mse_loss.detach().item()
+                log_data["lr"] = current_lr
+                log_data["grad"] = grad
+                if accelerator.sync_gradients:
+                    if use_wandb:
+                        wandb.log(log_data, step=global_step)
+                    if use_comet_ml:
+                        comet_experiment.log_metrics(log_data, step=global_step)
+
+                # Генерируем сэмплы с заданным интервалом
+                if global_step % sample_interval == 0:
+                    generate_and_save_samples(fixed_samples,global_step)
+                    last_n = sample_interval
+
+                    if save_model:
+                        avg_sample_loss = np.mean(batch_losses[-sample_interval:]) if len(batch_losses)>0 else 0.0
+                        print("saving:",avg_sample_loss < min_loss*save_barrier,"Current:",log_data["loss"],"Avg:",avg_sample_loss)
+                        if log_data["loss"] < min_loss*save_barrier:
+                            min_loss = avg_sample_loss
+                            save_checkpoint(unet)
+                    if use_wandb:
+                        wandb.log(log_data, step=global_step)
+                    if use_comet_ml:
+                        comet_experiment.log_metrics(log_data, step=global_step)
+
+
+    if accelerator.is_main_process:
+        avg_epoch_loss = np.mean(batch_losses[-steps_per_epoch:]) if len(batch_losses)>0 else 0.0
+        avg_epoch_grad = np.mean(batch_grads[-steps_per_epoch:]) if len(batch_grads)>0 else 0.0
+        print(f"\nЭпоха {epoch} завершена. Средний лосс: {avg_epoch_loss:.6f}")
+        if use_wandb:
+            wandb.log({"epoch_loss": avg_epoch_loss, "epoch_grad": avg_epoch_grad, "epoch": epoch+1})
+        #if use_comet_ml:
+        #    comet_experiment.log_metrics(epoch_data)
+
+# Завершение обучения - сохраняем финальную модель
+if accelerator.is_main_process:
+    print("Обучение завершено! Сохраняем финальную модель...")
+    if save_model:
+        save_checkpoint(unet,"fp16")
+    if use_comet_ml:
+        comet_experiment.end()
+accelerator.free_memory()
+if torch.distributed.is_initialized():
+    torch.distributed.destroy_process_group()
+    
+print("Готово!")

train.py

@@ -7,12 +7,11 @@ from torch.utils.data import DataLoader, Sampler
 from torch.utils.data.distributed import DistributedSampler
 from torch.optim.lr_scheduler import LambdaLR
 from collections import defaultdict
-from torch.optim.lr_scheduler import LambdaLR
-from diffusers import UNet2DConditionModel, AutoencoderKLWan,AutoencoderKL
+from diffusers import UNet2DConditionModel, AutoencoderKL
 from accelerate import Accelerator
 from datasets import load_from_disk
 from tqdm import tqdm
-from PIL import Image,ImageOps
+from PIL import Image, ImageOps
 import wandb
 import random
 import gc
@@ -45,8 +44,8 @@ unet_gradient = True
 clip_sample = False #Scheduler
 fixed_seed = True
 shuffle = True
-comet_ml_api_key = "Agctp26mbqnoYrrlvQuKSTk6r"  # Добавлен API ключ для Comet ML
-comet_ml_workspace = "recoilme"  # Добавлен workspace для Comet ML
+comet_ml_api_key = "Agctp26mbqnoYrrlvQuKSTk6r"
+comet_ml_workspace = "recoilme"
 torch.backends.cuda.matmul.allow_tf32 = True
 torch.backends.cudnn.allow_tf32 = True
 torch.backends.cuda.enable_mem_efficient_sdp(False)
@@ -60,7 +59,7 @@ clip_grad_norm = 1.0
 steps_offset = 0 # Scheduler
 limit = 0
 checkpoints_folder = ""
-mixed_precision = "no" #"fp16"
+mixed_precision = "no" # "fp16"
 gradient_accumulation_steps = 1
 accelerator = Accelerator(
     mixed_precision=mixed_precision,
@@ -88,7 +87,7 @@ if fixed_seed:
         torch.cuda.manual_seed_all(seed)
 
 # --------------------------- Параметры LoRA ---------------------------
-lora_name = "" 
+lora_name = ""
 lora_rank = 32
 lora_alpha = 64
 
@@ -103,13 +102,6 @@ def sample_timesteps_bias(
     device=None,
     mode: str = "beta",        # "beta", "uniform"
 ) -> torch.Tensor:
-    """
-    Возвращает timesteps с разным bias:
-    - beta   : как раньше (сдвиг в начало или конец в зависимости от progress)
-    - normal : около середины (гауссовое распределение)
-    - uniform: равномерно по всем timestep’ам
-    """
-
     max_idx = num_train_timesteps - 1 - steps_offset
 
     if mode == "beta":
@@ -126,17 +118,16 @@ def sample_timesteps_bias(
     timesteps = steps_offset + (samples * max_idx).long().to(device)
     return timesteps
 
+
 def logit_normal_samples(shape, mu=0.0, sigma=1.0, device=None, dtype=None):
     normal_samples = torch.normal(mean=mu, std=sigma, size=shape, device=device, dtype=dtype)
-
     logit_normal_samples = torch.sigmoid(normal_samples)
-
     return logit_normal_samples
 
 # --------------------------- Инициализация WandB ---------------------------
 if accelerator.is_main_process:
     if use_wandb:
-        wandb.init(project=project+lora_name, config={
+        wandb.init(project=project + lora_name, config={
             "batch_size": batch_size,
             "base_learning_rate": base_learning_rate,
             "num_epochs": num_epochs,
@@ -150,7 +141,6 @@ if accelerator.is_main_process:
             project_name=project,
             workspace=comet_ml_workspace
         )
-        # Логируем гиперпараметры в Comet ML
         hyper_params = {
             "batch_size": batch_size,
             "base_learning_rate": base_learning_rate,
@@ -170,8 +160,7 @@ gen = torch.Generator(device=device)
 gen.manual_seed(seed)
 
 # --------------------------- Загрузка моделей ---------------------------
-# VAE загружается на CPU для экономии GPU-памяти (как в твоём оригинальном коде)
-vae = AutoencoderKL.from_pretrained("AiArtLab/simplevae",subfolder="simple_vae_nightly",torch_dtype=dtype).to("cpu").eval()
+vae = AutoencoderKL.from_pretrained("AiArtLab/simplevae", subfolder="vae", torch_dtype=dtype).to("cpu").eval()
 
 shift_factor = getattr(vae.config, "shift_factor", 0.0)
 if shift_factor is None:
@@ -185,8 +174,6 @@ latents_mean = getattr(vae.config, "latents_mean", None)
 latents_std = getattr(vae.config, "latents_std", None)
 
 
-
-
 class DistributedResolutionBatchSampler(Sampler):
     def __init__(self, dataset, batch_size, num_replicas, rank, shuffle=True, drop_last=True):
         self.dataset = dataset
@@ -266,14 +253,16 @@ def get_fixed_samples_by_resolution(dataset, samples_per_group=1):
     fixed_samples = {}
     for size, indices in size_groups.items():
         n_samples = min(samples_per_group, len(indices))
-        if len(size_groups)==1:
+        if len(size_groups) == 1:
             n_samples = samples_to_generate
         if n_samples == 0:
             continue
         sample_indices = random.sample(indices, n_samples)
         samples_data = [dataset[idx] for idx in sample_indices]
-        latents = torch.tensor(np.array([item["vae"] for item in samples_data])).to(device=device,dtype=dtype)
-        embeddings = torch.tensor(np.array([item["embeddings"] for item in samples_data])).to(device,dtype=dtype)
+
+        # FIXED: keep fixed samples on CPU to avoid device/device-transfer issues when creating dataset
+        latents = torch.tensor(np.array([item["vae"] for item in samples_data]), dtype=dtype).cpu()
+        embeddings = torch.tensor(np.array([item["embeddings"] for item in samples_data]), dtype=dtype).cpu()
         texts = [item["text"] for item in samples_data]
         fixed_samples[size] = (latents, embeddings, texts)
     
@@ -285,9 +274,10 @@ if limit > 0:
 else:
     dataset = load_from_disk(ds_path)
 
+
 def collate_fn_simple(batch):
-    latents = torch.tensor(np.array([item["vae"] for item in batch])).to(device,dtype=dtype)
-    embeddings = torch.tensor(np.array([item["embeddings"] for item in batch])).to(device,dtype=dtype)
+    latents = torch.tensor(np.array([item["vae"] for item in batch]), dtype=dtype).to(device)
+    embeddings = torch.tensor(np.array([item["embeddings"] for item in batch]), dtype=dtype).to(device)
     return latents, embeddings
 
 batch_sampler = DistributedResolutionBatchSampler(
@@ -298,20 +288,23 @@ batch_sampler = DistributedResolutionBatchSampler(
         shuffle=shuffle
     )
 
+# NOTE: we create dataloader first, then prepare it with accelerator. We'll create optimizer/lr_scheduler after
+# we know len(dataloader) (which is per-process after prepare) so that scheduling is consistent.
+
 dataloader = DataLoader(dataset, batch_sampler=batch_sampler, collate_fn=collate_fn_simple)
-print("Total samples",len(dataloader))
+print("Total batches (pre-prepare):", len(dataloader))
 dataloader = accelerator.prepare(dataloader)
 
-start_epoch = 0
-global_step = 0
-total_training_steps = (len(dataloader) * num_epochs)
-world_size = accelerator.state.num_processes
+# --------------------------- Теперь безопасно --- вычисляем шаги и создаём оптимизатор/шедулер ---------------------------
+steps_per_epoch = len(dataloader)  # this is per-process (after prepare)
+total_training_steps = steps_per_epoch * num_epochs
+print(f"[rank {accelerator.process_index}] steps_per_epoch={steps_per_epoch}, total_training_steps={total_training_steps}")
 
-# Опция загрузки модели из последнего чекпоинта (если существует)
+# --------------------------- Создание/загрузка UNet ---------------------------
 latest_checkpoint = os.path.join(checkpoints_folder, project)
 if os.path.isdir(latest_checkpoint):
     print("Загружаем UNet из чекпоинта:", latest_checkpoint)
-    unet = UNet2DConditionModel.from_pretrained(latest_checkpoint).to(device=device,dtype=dtype)
+    unet = UNet2DConditionModel.from_pretrained(latest_checkpoint).to(device=device, dtype=dtype)
     if torch_compile:
         print("compiling")
         torch.set_float32_matmul_precision('high')
@@ -325,16 +318,14 @@ if os.path.isdir(latest_checkpoint):
     except Exception as e:
         print(f"Ошибка при включении SDPA: {e}")
         unet.set_use_memory_efficient_attention_xformers(True)
-
 else:
-    # FIX: если чекпоинта нет — прекращаем с понятной ошибкой (лучше, чем неожиданные NameError дальше)
     raise FileNotFoundError(f"UNet checkpoint not found at {latest_checkpoint}. Положи UNet чекпоинт в {latest_checkpoint} или укажи другой путь.")
 
+# --------------------------- LoRA (если нужно) ---------------------------
 if lora_name:
     print(f"--- Настройка LoRA через PEFT (Rank={lora_rank}, Alpha={lora_alpha}) ---")
     from peft import LoraConfig, get_peft_model, prepare_model_for_kbit_training
     from peft.tuners.lora import LoraModel
-    import os
     unet.requires_grad_(False)
     print("Параметры базового UNet заморожены.")
 
@@ -372,8 +363,8 @@ if lora_name:
 if lora_name:
     trainable_params = [p for p in unet.parameters() if p.requires_grad]
 else:
-    if fbp:
-        trainable_params = list(unet.parameters())
+    trainable_params = list(unet.parameters()) if fbp else [p for p in unet.parameters() if p.requires_grad]
+
 
 def create_optimizer(name, params):
     if name == "adam8bit":
@@ -407,11 +398,15 @@ if fbp:
         optimizer_dict[param].zero_grad(set_to_none=True)
     for param in trainable_params:
         param.register_post_accumulate_grad_hook(optimizer_hook)
+    # FIXED: prepare fbp variant (keeps original logic)
     unet, optimizer = accelerator.prepare(unet, optimizer_dict)
 else:
-    optimizer = create_optimizer(optimizer_type, unet.parameters())
+    optimizer = create_optimizer(optimizer_type, trainable_params)
+
+    # FIXED: LR schedule should be based on total_training_steps (per-process steps * epochs)
     def lr_schedule(step):
-        x = step / (total_training_steps * world_size)
+        # step is current scheduler step (0..total_training_steps)
+        x = step / max(1, total_training_steps)
         warmup = warmup_percent
         if not use_decay:
             return base_learning_rate
@@ -420,6 +415,8 @@ else:
         decay_ratio = (x - warmup) / (1 - warmup)
         return min_learning_rate + 0.5 * (base_learning_rate - min_learning_rate) * \
                (1 + math.cos(math.pi * decay_ratio))
+
+    # LambdaLR expects a multiplier, so divide by base_learning_rate
     lr_scheduler = LambdaLR(optimizer, lambda step: lr_schedule(step) / base_learning_rate)
 
     num_params = sum(p.numel() for p in unet.parameters())
@@ -427,12 +424,13 @@ else:
     for name, param in unet.named_parameters():
         if torch.isnan(param).any() or torch.isinf(param).any():
             print(f"[rank {accelerator.process_index}] NaN/Inf in {name}")
+
+    # FIXED: prepare model, optimizer, scheduler AFTER creating them and after dataloader.prepare
     unet, optimizer, lr_scheduler = accelerator.prepare(unet, optimizer, lr_scheduler)
 
 # --------------------------- Фиксированные семплы для генерации ---------------------------
 fixed_samples = get_fixed_samples_by_resolution(dataset)
 
-@torch.compiler.disable()
 @torch.no_grad()
 def generate_and_save_samples(fixed_samples_cpu, step):
     original_model = None
@@ -440,12 +438,12 @@ def generate_and_save_samples(fixed_samples_cpu, step):
         original_model = accelerator.unwrap_model(unet, keep_torch_compile=True).eval()
         vae.to(device=device).eval()  # временно подгружаем VAE на GPU для декодинга
 
-        
         all_generated_images = []
         all_captions = [] 
         
         for size, (sample_latents, sample_text_embeddings, sample_text) in fixed_samples_cpu.items():
             width, height = size
+            # move CPU tensors to device here (they were kept on CPU in get_fixed_samples_by_resolution)
             sample_latents = sample_latents.to(dtype=dtype, device=device)
             sample_text_embeddings = sample_text_embeddings.to(dtype=dtype, device=device)
 
@@ -484,19 +482,11 @@ def generate_and_save_samples(fixed_samples_cpu, step):
 
             # Параметры нормализации
             latent_for_vae = current_latents.detach() / scaling_factor + shift_factor
-            
             decoded = vae.decode(latent_for_vae.to(torch.float32)).sample
-            #decoded = decoded[:, :, 0, :, :]  # [3, H, W]
-            #print(decoded.ndim, decoded.shape)
-            
             decoded_fp32 = decoded.to(torch.float32)
             for img_idx, img_tensor in enumerate(decoded_fp32):
-
-                # Форма: [3, H, W] -> преобразуем в [H, W, 3]
                 img = (img_tensor / 2 + 0.5).clamp(0, 1).cpu().numpy()
-                img = img.transpose(1, 2, 0)  # Из [3, H, W] в [H, W, 3]
-    
-                #img = (img_tensor / 2 + 0.5).clamp(0, 1).cpu().numpy().transpose(1, 2, 0)
+                img = img.transpose(1, 2, 0)
                 if np.isnan(img).any():
                     print("NaNs found, saving stopped! Step:", step)
                 pil_img = Image.fromarray((img * 255).astype("uint8"))
@@ -520,7 +510,7 @@ def generate_and_save_samples(fixed_samples_cpu, step):
                 wandb.Image(img, caption=f"{all_captions[i]}")
                 for i, img in enumerate(all_generated_images)
             ]
-            wandb.log({"generated_images": wandb_images})
+            wandb.log({"generated_images": wandb_images}, step=step)
         if use_comet_ml and accelerator.is_main_process:
             for i, img in enumerate(all_generated_images):
                 comet_experiment.log_image(
@@ -535,11 +525,7 @@ def generate_and_save_samples(fixed_samples_cpu, step):
                     }
                 )
     finally:
-        # вернуть VAE на CPU (как было в твоём коде)
         vae.to("cpu")
-        for var in list(locals().keys()):
-            if isinstance(locals()[var], torch.Tensor):
-                del locals()[var]
         torch.cuda.empty_cache()
         gc.collect()
 
@@ -547,20 +533,23 @@ def generate_and_save_samples(fixed_samples_cpu, step):
 if accelerator.is_main_process:
     if save_model:
         print("Генерация сэмплов до старта обучения...")
-        generate_and_save_samples(fixed_samples,0)
+        generate_and_save_samples(fixed_samples, 0)
 accelerator.wait_for_everyone()
 
 # Модифицируем функцию сохранения модели для поддержки LoRA
-def save_checkpoint(unet,variant=""):
+def save_checkpoint(unet, variant=""):
     if accelerator.is_main_process:
         if lora_name:
             save_lora_checkpoint(unet)
         else:
-            if variant!="":
-                accelerator.unwrap_model(unet.to(dtype=torch.float16)).save_pretrained(os.path.join(checkpoints_folder, f"{project}"),variant=variant)
+            # FIXED: don't change dtype of model wrapped by accelerator. Unwrap and save as-is.
+            model_to_save = accelerator.unwrap_model(unet)
+            dest = os.path.join(checkpoints_folder, f"{project}")
+            if variant != "":
+                model_to_save.save_pretrained(dest, variant=variant)
             else:
-                accelerator.unwrap_model(unet).save_pretrained(os.path.join(checkpoints_folder, f"{project}"))
-            unet = unet.to(dtype=dtype)
+                model_to_save.save_pretrained(dest)
+
 
 # --------------------------- Тренировочный цикл ---------------------------
 if accelerator.is_main_process:
@@ -569,20 +558,25 @@ if accelerator.is_main_process:
 epoch_loss_points = []
 progress_bar = tqdm(total=total_training_steps, disable=not accelerator.is_local_main_process, desc="Training", unit="step")
 
-steps_per_epoch = len(dataloader)
 sample_interval = max(1, steps_per_epoch // sample_interval_share)
 min_loss = 2.
 
-for epoch in range(start_epoch, start_epoch + num_epochs):
-    batch_losses = []
-    batch_grads = []
-    batch_sampler.set_epoch(epoch)
+for epoch in range(0, num_epochs):
+    # FIXED: set epoch on the dataloader's batch_sampler if available (accelerator may have wrapped it)
+    if hasattr(dataloader, "batch_sampler") and hasattr(dataloader.batch_sampler, "set_epoch"):
+        dataloader.batch_sampler.set_epoch(epoch)
+    elif hasattr(batch_sampler, "set_epoch"):
+        batch_sampler.set_epoch(epoch)
+
     accelerator.wait_for_everyone()
     unet.train()
-    #print("epoch:",epoch)
+
+    batch_losses = []
+    batch_grads = []
+
     for step, (latents, embeddings) in enumerate(dataloader):
         with accelerator.accumulate(unet):
-            if save_model == False and step == 5 :
+            if save_model == False and step == 5:
                 used_gb = torch.cuda.max_memory_allocated() / 1024**3
                 print(f"Шаг {step}: {used_gb:.2f} GB")
                 
@@ -596,80 +590,94 @@ for epoch in range(start_epoch, start_epoch + num_epochs):
 
             mse_loss = F.mse_loss(model_pred.float(), target_pred.float())
 
-            # Сохраняем для логов (мы сохраняем MSE отдельно — как показатель)
-            batch_losses.append(mse_loss.detach().item())
+            # Сохраняем для локальных логов
+            batch_losses.append(mse_loss.detach().cpu().item())
 
-            if (global_step % 100 == 0) or (global_step % sample_interval == 0):
-                accelerator.wait_for_everyone()
-                
             # Backward
             accelerator.backward(mse_loss)
 
-            if (global_step % 100 == 0) or (global_step % sample_interval == 0):
-                accelerator.wait_for_everyone()
-                
-            grad = 0.0
+            grad_norm_val = 0.0
             if not fbp:
                 if accelerator.sync_gradients:
-                    with torch.amp.autocast('cuda', enabled=False):
-                        grad_val = accelerator.clip_grad_norm_(unet.parameters(), clip_grad_norm)
-                    grad = float(grad_val)
+                    # Clip gradients and step only when gradients are synchronized (i.e. actual optimizer step)
+                    grad_norm = accelerator.clip_grad_norm_(unet.parameters(), clip_grad_norm)
+                    grad_norm_val = float(grad_norm)
                     optimizer.step()
                     lr_scheduler.step()
                     optimizer.zero_grad(set_to_none=True)
 
-            global_step += 1
-            progress_bar.update(1)
-
-            # Логируем метрики
-            if accelerator.is_main_process:
-                if fbp:
-                    current_lr = base_learning_rate
+            # increment global_step only when we have synchronized gradients (i.e. on optimizer step)
+            # FIXED: ensure global_step reflects optimizer updates, not micro-batches
+            if accelerator.sync_gradients:
+                try:
+                    global_step += 1
+                except NameError:
+                    global_step = 1
+                progress_bar.update(1)
+
+                # Aggregate loss across processes for correct logging
+                loss_tensor = mse_loss.detach().clone()
+                # move to device if not already
+                loss_tensor = loss_tensor.to(device)
+                gathered = accelerator.gather(loss_tensor)
+                if accelerator.is_main_process:
+                    reduced_loss = gathered.mean().item()
                 else:
-                    current_lr = lr_scheduler.get_last_lr()[0]
-                batch_grads.append(grad)
-
-                log_data = {}
-                log_data["loss"] = mse_loss.detach().item()
-                log_data["lr"] = current_lr
-                log_data["grad"] = grad
-                if accelerator.sync_gradients:
-                    if use_wandb:
-                        wandb.log(log_data, step=global_step)
-                    if use_comet_ml:
-                        comet_experiment.log_metrics(log_data, step=global_step)
+                    reduced_loss = None
+
+                # Логируем метрики только на главном процессе
+                if accelerator.is_main_process:
+                    if fbp:
+                        current_lr = base_learning_rate
+                    else:
+                        current_lr = lr_scheduler.get_last_lr()[0]
+
+                    batch_grads.append(grad_norm_val)
+
+                    log_data = {
+                        "loss": reduced_loss,
+                        "lr": current_lr,
+                        "grad": grad_norm_val,
+                        "epoch": epoch + 1,
+                        "global_step": global_step,
+                    }
 
-                # Генерируем сэмплы с заданным интервалом
-                if global_step % sample_interval == 0:
-                    generate_and_save_samples(fixed_samples,global_step)
-                    last_n = sample_interval
-
-                    if save_model:
-                        avg_sample_loss = np.mean(batch_losses[-sample_interval:]) if len(batch_losses)>0 else 0.0
-                        print("saving:",avg_sample_loss < min_loss*save_barrier,"Current:",log_data["loss"],"Avg:",avg_sample_loss)
-                        if log_data["loss"] < min_loss*save_barrier:
-                            min_loss = avg_sample_loss
-                            save_checkpoint(unet)
                     if use_wandb:
                         wandb.log(log_data, step=global_step)
                     if use_comet_ml:
                         comet_experiment.log_metrics(log_data, step=global_step)
 
-
+                    # Генерируем сэмплы с заданным интервалом (только на главном процессе)
+                    if global_step % sample_interval == 0:
+                        generate_and_save_samples(fixed_samples, global_step)
+
+                        if save_model:
+                            # use recent local losses to decide saving (still local); you may want to use reduced_loss here
+                            avg_sample_loss = np.mean(batch_losses[-sample_interval:]) if len(batch_losses) > 0 else 0.0
+                            if use_wandb:
+                                wandb.log({"sample_loss": avg_sample_loss)
+                            print("saving:", reduced_loss is not None and reduced_loss < min_loss * save_barrier, "Current:", reduced_loss, "Avg:", avg_sample_loss)
+                            if reduced_loss is not None and reduced_loss < min_loss * save_barrier:
+                                min_loss = avg_sample_loss
+                                save_checkpoint(unet)
+
+    # Эпоха окончена — агрегируем и логируем средние значения
     if accelerator.is_main_process:
-        avg_epoch_loss = np.mean(batch_losses[-steps_per_epoch:]) if len(batch_losses)>0 else 0.0
-        avg_epoch_grad = np.mean(batch_grads[-steps_per_epoch:]) if len(batch_grads)>0 else 0.0
-        print(f"\nЭпоха {epoch} завершена. Средний лосс: {avg_epoch_loss:.6f}")
+        # local averages
+        avg_epoch_loss = np.mean(batch_losses) if len(batch_losses) > 0 else 0.0
+        avg_epoch_grad = np.mean(batch_grads) if len(batch_grads) > 0 else 0.0
+
+        # FIXED: optionally reduce across processes if you want a true global epoch average
+        # Here we compute local values and log them (main process only). For global average use accelerator.gather
+        print(f"\nЭпоха {epoch} завершена. Средний лосс (local main proc): {avg_epoch_loss:.6f}")
         if use_wandb:
-            wandb.log({"epoch_loss": avg_epoch_loss, "epoch_grad": avg_epoch_grad, "epoch": epoch+1})
-        #if use_comet_ml:
-        #    comet_experiment.log_metrics(epoch_data)
+            wandb.log({"epoch_loss": avg_epoch_loss, "epoch_grad": avg_epoch_grad, "epoch": epoch + 1})
 
 # Завершение обучения - сохраняем финальную модель
 if accelerator.is_main_process:
     print("Обучение завершено! Сохраняем финальную модель...")
     if save_model:
-        save_checkpoint(unet,"fp16")
+        save_checkpoint(unet, "fp16")
     if use_comet_ml:
         comet_experiment.end()
 accelerator.free_memory()

unet/diffusion_pytorch_model.safetensors

@@ -1,3 +1,3 @@
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