import importlib import argparse import gc import math import os import random import time import json from tqdm import tqdm import torch from accelerate.utils import set_seed import diffusers from diffusers import DDPMScheduler import library.train_util as train_util from library.train_util import DreamBoothDataset, FineTuningDataset def collate_fn(examples): return examples[0] def generate_step_logs(args: argparse.Namespace, current_loss, avr_loss, lr_scheduler): logs = {"loss/current": current_loss, "loss/average": avr_loss} if args.network_train_unet_only: logs["lr/unet"] = lr_scheduler.get_last_lr()[0] elif args.network_train_text_encoder_only: logs["lr/textencoder"] = lr_scheduler.get_last_lr()[0] else: logs["lr/textencoder"] = lr_scheduler.get_last_lr()[0] logs["lr/unet"] = lr_scheduler.get_last_lr()[-1] # may be same to textencoder return logs def train(args): session_id = random.randint(0, 2**32) training_started_at = time.time() train_util.verify_training_args(args) train_util.prepare_dataset_args(args, True) cache_latents = args.cache_latents use_dreambooth_method = args.in_json is None if args.seed is not None: set_seed(args.seed) tokenizer = train_util.load_tokenizer(args) # データセットを準備する if use_dreambooth_method: print("Use DreamBooth method.") train_dataset = DreamBoothDataset(args.train_batch_size, args.train_data_dir, args.reg_data_dir, tokenizer, args.max_token_length, args.caption_extension, args.shuffle_caption, args.keep_tokens, args.resolution, args.enable_bucket, args.min_bucket_reso, args.max_bucket_reso, args.prior_loss_weight, args.flip_aug, args.color_aug, args.face_crop_aug_range, args.random_crop, args.debug_dataset) else: print("Train with captions.") train_dataset = FineTuningDataset(args.in_json, args.train_batch_size, args.train_data_dir, tokenizer, args.max_token_length, args.shuffle_caption, args.keep_tokens, args.resolution, args.enable_bucket, args.min_bucket_reso, args.max_bucket_reso, args.flip_aug, args.color_aug, args.face_crop_aug_range, args.random_crop, args.dataset_repeats, args.debug_dataset) train_dataset.make_buckets() if args.debug_dataset: train_util.debug_dataset(train_dataset) return if len(train_dataset) == 0: print("No data found. Please verify arguments / 画像がありません。引数指定を確認してください") return # acceleratorを準備する print("prepare accelerator") accelerator, unwrap_model = train_util.prepare_accelerator(args) # mixed precisionに対応した型を用意しておき適宜castする weight_dtype, save_dtype = train_util.prepare_dtype(args) # モデルを読み込む text_encoder, vae, unet, _ = train_util.load_target_model(args, weight_dtype) # モデルに xformers とか memory efficient attention を組み込む train_util.replace_unet_modules(unet, args.mem_eff_attn, args.xformers) # 学習を準備する if cache_latents: vae.to(accelerator.device, dtype=weight_dtype) vae.requires_grad_(False) vae.eval() with torch.no_grad(): train_dataset.cache_latents(vae) vae.to("cpu") if torch.cuda.is_available(): torch.cuda.empty_cache() gc.collect() # prepare network print("import network module:", args.network_module) network_module = importlib.import_module(args.network_module) net_kwargs = {} if args.network_args is not None: for net_arg in args.network_args: key, value = net_arg.split('=') net_kwargs[key] = value # if a new network is added in future, add if ~ then blocks for each network (;'∀') network = network_module.create_network(1.0, args.network_dim, args.network_alpha, vae, text_encoder, unet, **net_kwargs) if network is None: return if args.network_weights is not None: print("load network weights from:", args.network_weights) network.load_weights(args.network_weights) train_unet = not args.network_train_text_encoder_only train_text_encoder = not args.network_train_unet_only network.apply_to(text_encoder, unet, train_text_encoder, train_unet) if args.gradient_checkpointing: unet.enable_gradient_checkpointing() text_encoder.gradient_checkpointing_enable() network.enable_gradient_checkpointing() # may have no effect # 学習に必要なクラスを準備する print("prepare optimizer, data loader etc.") # 8-bit Adamを使う if args.use_8bit_adam: try: import bitsandbytes as bnb except ImportError: raise ImportError("No bitsand bytes / bitsandbytesがインストールされていないようです") print("use 8-bit Adam optimizer") optimizer_class = bnb.optim.AdamW8bit else: optimizer_class = torch.optim.AdamW trainable_params = network.prepare_optimizer_params(args.text_encoder_lr, args.unet_lr) # betaやweight decayはdiffusers DreamBoothもDreamBooth SDもデフォルト値のようなのでオプションはとりあえず省略 optimizer = optimizer_class(trainable_params, lr=args.learning_rate) # dataloaderを準備する # DataLoaderのプロセス数：0はメインプロセスになる n_workers = min(args.max_data_loader_n_workers, os.cpu_count() - 1) # cpu_count-1 ただし最大で指定された数まで train_dataloader = torch.utils.data.DataLoader( train_dataset, batch_size=1, shuffle=False, collate_fn=collate_fn, num_workers=n_workers) # 学習ステップ数を計算する if args.max_train_epochs is not None: args.max_train_steps = args.max_train_epochs * len(train_dataloader) print(f"override steps. steps for {args.max_train_epochs} epochs is / 指定エポックまでのステップ数: {args.max_train_steps}") # lr schedulerを用意する lr_scheduler = diffusers.optimization.get_scheduler( args.lr_scheduler, optimizer, num_warmup_steps=args.lr_warmup_steps, num_training_steps=args.max_train_steps * args.gradient_accumulation_steps) # 実験的機能：勾配も含めたfp16学習を行う　モデル全体をfp16にする if args.full_fp16: assert args.mixed_precision == "fp16", "full_fp16 requires mixed precision='fp16' / full_fp16を使う場合はmixed_precision='fp16'を指定してください。" print("enable full fp16 training.") network.to(weight_dtype) # acceleratorがなんかよろしくやってくれるらしい if train_unet and train_text_encoder: unet, text_encoder, network, optimizer, train_dataloader, lr_scheduler = accelerator.prepare( unet, text_encoder, network, optimizer, train_dataloader, lr_scheduler) elif train_unet: unet, network, optimizer, train_dataloader, lr_scheduler = accelerator.prepare( unet, network, optimizer, train_dataloader, lr_scheduler) elif train_text_encoder: text_encoder, network, optimizer, train_dataloader, lr_scheduler = accelerator.prepare( text_encoder, network, optimizer, train_dataloader, lr_scheduler) else: network, optimizer, train_dataloader, lr_scheduler = accelerator.prepare( network, optimizer, train_dataloader, lr_scheduler) unet.requires_grad_(False) unet.to(accelerator.device, dtype=weight_dtype) text_encoder.requires_grad_(False) text_encoder.to(accelerator.device, dtype=weight_dtype) if args.gradient_checkpointing: # according to TI example in Diffusers, train is required unet.train() text_encoder.train() # set top parameter requires_grad = True for gradient checkpointing works text_encoder.text_model.embeddings.requires_grad_(True) else: unet.eval() text_encoder.eval() network.prepare_grad_etc(text_encoder, unet) if not cache_latents: vae.requires_grad_(False) vae.eval() vae.to(accelerator.device, dtype=weight_dtype) # 実験的機能：勾配も含めたfp16学習を行う　PyTorchにパッチを当ててfp16でのgrad scaleを有効にする if args.full_fp16: train_util.patch_accelerator_for_fp16_training(accelerator) # resumeする if args.resume is not None: print(f"resume training from state: {args.resume}") accelerator.load_state(args.resume) # epoch数を計算する num_update_steps_per_epoch = math.ceil(len(train_dataloader) / args.gradient_accumulation_steps) num_train_epochs = math.ceil(args.max_train_steps / num_update_steps_per_epoch) # 学習する total_batch_size = args.train_batch_size * accelerator.num_processes * args.gradient_accumulation_steps print("running training / 学習開始") print(f" num train images * repeats / 学習画像の数×繰り返し回数: {train_dataset.num_train_images}") print(f" num reg images / 正則化画像の数: {train_dataset.num_reg_images}") print(f" num batches per epoch / 1epochのバッチ数: {len(train_dataloader)}") print(f" num epochs / epoch数: {num_train_epochs}") print(f" batch size per device / バッチサイズ: {args.train_batch_size}") print(f" total train batch size (with parallel & distributed & accumulation) / 総バッチサイズ（並列学習、勾配合計含む）: {total_batch_size}") print(f" gradient accumulation steps / 勾配を合計するステップ数 = {args.gradient_accumulation_steps}") print(f" total optimization steps / 学習ステップ数: {args.max_train_steps}") metadata = { "ss_session_id": session_id, # random integer indicating which group of epochs the model came from "ss_training_started_at": training_started_at, # unix timestamp "ss_output_name": args.output_name, "ss_learning_rate": args.learning_rate, "ss_text_encoder_lr": args.text_encoder_lr, "ss_unet_lr": args.unet_lr, "ss_num_train_images": train_dataset.num_train_images, # includes repeating "ss_num_reg_images": train_dataset.num_reg_images, "ss_num_batches_per_epoch": len(train_dataloader), "ss_num_epochs": num_train_epochs, "ss_batch_size_per_device": args.train_batch_size, "ss_total_batch_size": total_batch_size, "ss_gradient_checkpointing": args.gradient_checkpointing, "ss_gradient_accumulation_steps": args.gradient_accumulation_steps, "ss_max_train_steps": args.max_train_steps, "ss_lr_warmup_steps": args.lr_warmup_steps, "ss_lr_scheduler": args.lr_scheduler, "ss_network_module": args.network_module, "ss_network_dim": args.network_dim, # None means default because another network than LoRA may have another default dim "ss_network_alpha": args.network_alpha, # some networks may not use this value "ss_mixed_precision": args.mixed_precision, "ss_full_fp16": bool(args.full_fp16), "ss_v2": bool(args.v2), "ss_resolution": args.resolution, "ss_clip_skip": args.clip_skip, "ss_max_token_length": args.max_token_length, "ss_color_aug": bool(args.color_aug), "ss_flip_aug": bool(args.flip_aug), "ss_random_crop": bool(args.random_crop), "ss_shuffle_caption": bool(args.shuffle_caption), "ss_cache_latents": bool(args.cache_latents), "ss_enable_bucket": bool(train_dataset.enable_bucket), "ss_min_bucket_reso": train_dataset.min_bucket_reso, "ss_max_bucket_reso": train_dataset.max_bucket_reso, "ss_seed": args.seed, "ss_keep_tokens": args.keep_tokens, "ss_dataset_dirs": json.dumps(train_dataset.dataset_dirs_info), "ss_reg_dataset_dirs": json.dumps(train_dataset.reg_dataset_dirs_info), "ss_training_comment": args.training_comment # will not be updated after training } # uncomment if another network is added # for key, value in net_kwargs.items(): # metadata["ss_arg_" + key] = value if args.pretrained_model_name_or_path is not None: sd_model_name = args.pretrained_model_name_or_path if os.path.exists(sd_model_name): metadata["ss_sd_model_hash"] = train_util.model_hash(sd_model_name) metadata["ss_new_sd_model_hash"] = train_util.calculate_sha256(sd_model_name) sd_model_name = os.path.basename(sd_model_name) metadata["ss_sd_model_name"] = sd_model_name if args.vae is not None: vae_name = args.vae if os.path.exists(vae_name): metadata["ss_vae_hash"] = train_util.model_hash(vae_name) metadata["ss_new_vae_hash"] = train_util.calculate_sha256(vae_name) vae_name = os.path.basename(vae_name) metadata["ss_vae_name"] = vae_name metadata = {k: str(v) for k, v in metadata.items()} progress_bar = tqdm(range(args.max_train_steps), smoothing=0, disable=not accelerator.is_local_main_process, desc="steps") global_step = 0 noise_scheduler = DDPMScheduler(beta_start=0.00085, beta_end=0.012, beta_schedule="scaled_linear", num_train_timesteps=1000, clip_sample=False) if accelerator.is_main_process: accelerator.init_trackers("network_train") for epoch in range(num_train_epochs): print(f"epoch {epoch+1}/{num_train_epochs}") metadata["ss_epoch"] = str(epoch+1) network.on_epoch_start(text_encoder, unet) loss_total = 0 for step, batch in enumerate(train_dataloader): with accelerator.accumulate(network): with torch.no_grad(): if "latents" in batch and batch["latents"] is not None: latents = batch["latents"].to(accelerator.device) else: # latentに変換 latents = vae.encode(batch["images"].to(dtype=weight_dtype)).latent_dist.sample() latents = latents * 0.18215 b_size = latents.shape[0] with torch.set_grad_enabled(train_text_encoder): # Get the text embedding for conditioning input_ids = batch["input_ids"].to(accelerator.device) encoder_hidden_states = train_util.get_hidden_states(args, input_ids, tokenizer, text_encoder, weight_dtype) # Sample noise that we'll add to the latents noise = torch.randn_like(latents, device=latents.device) # Sample a random timestep for each image timesteps = torch.randint(0, noise_scheduler.config.num_train_timesteps, (b_size,), device=latents.device) timesteps = timesteps.long() # Add noise to the latents according to the noise magnitude at each timestep # (this is the forward diffusion process) noisy_latents = noise_scheduler.add_noise(latents, noise, timesteps) # Predict the noise residual noise_pred = unet(noisy_latents, timesteps, encoder_hidden_states).sample if args.v_parameterization: # v-parameterization training target = noise_scheduler.get_velocity(latents, noise, timesteps) else: target = noise loss = torch.nn.functional.mse_loss(noise_pred.float(), target.float(), reduction="none") loss = loss.mean([1, 2, 3]) loss_weights = batch["loss_weights"] # 各sampleごとのweight loss = loss * loss_weights loss = loss.mean() # 平均なのでbatch_sizeで割る必要なし accelerator.backward(loss) if accelerator.sync_gradients: params_to_clip = network.get_trainable_params() accelerator.clip_grad_norm_(params_to_clip, 1.0) # args.max_grad_norm) optimizer.step() lr_scheduler.step() optimizer.zero_grad(set_to_none=True) # Checks if the accelerator has performed an optimization step behind the scenes if accelerator.sync_gradients: progress_bar.update(1) global_step += 1 current_loss = loss.detach().item() loss_total += current_loss avr_loss = loss_total / (step+1) logs = {"loss": avr_loss} # , "lr": lr_scheduler.get_last_lr()[0]} progress_bar.set_postfix(**logs) if args.logging_dir is not None: logs = generate_step_logs(args, current_loss, avr_loss, lr_scheduler) accelerator.log(logs, step=global_step) if global_step >= args.max_train_steps: break if args.logging_dir is not None: logs = {"loss/epoch": loss_total / len(train_dataloader)} accelerator.log(logs, step=epoch+1) accelerator.wait_for_everyone() if args.save_every_n_epochs is not None: model_name = train_util.DEFAULT_EPOCH_NAME if args.output_name is None else args.output_name def save_func(): ckpt_name = train_util.EPOCH_FILE_NAME.format(model_name, epoch + 1) + '.' + args.save_model_as ckpt_file = os.path.join(args.output_dir, ckpt_name) print(f"saving checkpoint: {ckpt_file}") unwrap_model(network).save_weights(ckpt_file, save_dtype, None if args.no_metadata else metadata) def remove_old_func(old_epoch_no): old_ckpt_name = train_util.EPOCH_FILE_NAME.format(model_name, old_epoch_no) + '.' + args.save_model_as old_ckpt_file = os.path.join(args.output_dir, old_ckpt_name) if os.path.exists(old_ckpt_file): print(f"removing old checkpoint: {old_ckpt_file}") os.remove(old_ckpt_file) saving = train_util.save_on_epoch_end(args, save_func, remove_old_func, epoch + 1, num_train_epochs) if saving and args.save_state: train_util.save_state_on_epoch_end(args, accelerator, model_name, epoch + 1) # end of epoch metadata["ss_epoch"] = str(num_train_epochs) is_main_process = accelerator.is_main_process if is_main_process: network = unwrap_model(network) accelerator.end_training() if args.save_state: train_util.save_state_on_train_end(args, accelerator) del accelerator # この後メモリを使うのでこれは消す if is_main_process: os.makedirs(args.output_dir, exist_ok=True) model_name = train_util.DEFAULT_LAST_OUTPUT_NAME if args.output_name is None else args.output_name ckpt_name = model_name + '.' + args.save_model_as ckpt_file = os.path.join(args.output_dir, ckpt_name) print(f"save trained model to {ckpt_file}") network.save_weights(ckpt_file, save_dtype, None if args.no_metadata else metadata) print("model saved.") if __name__ == '__main__': parser = argparse.ArgumentParser() train_util.add_sd_models_arguments(parser) train_util.add_dataset_arguments(parser, True, True) train_util.add_training_arguments(parser, True) parser.add_argument("--no_metadata", action='store_true', help="do not save metadata in output model / メタデータを出力先モデルに保存しない") parser.add_argument("--save_model_as", type=str, default="pt", choices=[None, "ckpt", "pt", "safetensors"], help="format to save the model (default is .pt) / モデル保存時の形式（デフォルトはpt）") parser.add_argument("--unet_lr", type=float, default=None, help="learning rate for U-Net / U-Netの学習率") parser.add_argument("--text_encoder_lr", type=float, default=None, help="learning rate for Text Encoder / Text Encoderの学習率") parser.add_argument("--network_weights", type=str, default=None, help="pretrained weights for network / 学習するネットワークの初期重み") parser.add_argument("--network_module", type=str, default=None, help='network module to train / 学習対象のネットワークのモジュール') parser.add_argument("--network_dim", type=int, default=None, help='network dimensions (depends on each network) / モジュールの次元数（ネットワークにより定義は異なります）') parser.add_argument("--network_alpha", type=float, default=1, help='alpha for LoRA weight scaling, default 1 (same as network_dim for same behavior as old version) / LoRaの重み調整のalpha値、デフォルト1（旧バージョンと同じ動作をするにはnetwork_dimと同じ値を指定）') parser.add_argument("--network_args", type=str, default=None, nargs='*', help='additional argmuments for network (key=value) / ネットワークへの追加の引数') parser.add_argument("--network_train_unet_only", action="store_true", help="only training U-Net part / U-Net関連部分のみ学習する") parser.add_argument("--network_train_text_encoder_only", action="store_true", help="only training Text Encoder part / Text Encoder関連部分のみ学習する") parser.add_argument("--training_comment", type=str, default=None, help="arbitrary comment string stored in metadata / メタデータに記録する任意のコメント文字列") args = parser.parse_args() train(args)