import math import argparse import os import time import torch from safetensors.torch import load_file, save_file from tqdm import tqdm from library import sai_model_spec, train_util import library.model_util as model_util import lora CLAMP_QUANTILE = 0.99 def load_state_dict(file_name, dtype): if os.path.splitext(file_name)[1] == ".safetensors": sd = load_file(file_name) metadata = train_util.load_metadata_from_safetensors(file_name) else: sd = torch.load(file_name, map_location="cpu") metadata = {} for key in list(sd.keys()): if type(sd[key]) == torch.Tensor: sd[key] = sd[key].to(dtype) return sd, metadata def save_to_file(file_name, state_dict, dtype, metadata): if dtype is not None: for key in list(state_dict.keys()): if type(state_dict[key]) == torch.Tensor: state_dict[key] = state_dict[key].to(dtype) if os.path.splitext(file_name)[1] == ".safetensors": save_file(state_dict, file_name, metadata=metadata) else: torch.save(state_dict, file_name) def merge_lora_models(models, ratios, new_rank, new_conv_rank, device, merge_dtype): print(f"new rank: {new_rank}, new conv rank: {new_conv_rank}") merged_sd = {} v2 = None base_model = None for model, ratio in zip(models, ratios): print(f"loading: {model}") lora_sd, lora_metadata = load_state_dict(model, merge_dtype) if lora_metadata is not None: if v2 is None: v2 = lora_metadata.get(train_util.SS_METADATA_KEY_V2, None) # return string if base_model is None: base_model = lora_metadata.get(train_util.SS_METADATA_KEY_BASE_MODEL_VERSION, None) # merge print(f"merging...") for key in tqdm(list(lora_sd.keys())): if "lora_down" not in key: continue lora_module_name = key[: key.rfind(".lora_down")] down_weight = lora_sd[key] network_dim = down_weight.size()[0] up_weight = lora_sd[lora_module_name + ".lora_up.weight"] alpha = lora_sd.get(lora_module_name + ".alpha", network_dim) in_dim = down_weight.size()[1] out_dim = up_weight.size()[0] conv2d = len(down_weight.size()) == 4 kernel_size = None if not conv2d else down_weight.size()[2:4] # print(lora_module_name, network_dim, alpha, in_dim, out_dim, kernel_size) # make original weight if not exist if lora_module_name not in merged_sd: weight = torch.zeros((out_dim, in_dim, *kernel_size) if conv2d else (out_dim, in_dim), dtype=merge_dtype) if device: weight = weight.to(device) else: weight = merged_sd[lora_module_name] # merge to weight if device: up_weight = up_weight.to(device) down_weight = down_weight.to(device) # W <- W + U * D scale = alpha / network_dim if device: # and isinstance(scale, torch.Tensor): scale = scale.to(device) if not conv2d: # linear weight = weight + ratio * (up_weight @ down_weight) * scale elif kernel_size == (1, 1): weight = ( weight + ratio * (up_weight.squeeze(3).squeeze(2) @ down_weight.squeeze(3).squeeze(2)).unsqueeze(2).unsqueeze(3) * scale ) else: conved = torch.nn.functional.conv2d(down_weight.permute(1, 0, 2, 3), up_weight).permute(1, 0, 2, 3) weight = weight + ratio * conved * scale merged_sd[lora_module_name] = weight # extract from merged weights print("extract new lora...") merged_lora_sd = {} with torch.no_grad(): for lora_module_name, mat in tqdm(list(merged_sd.items())): conv2d = len(mat.size()) == 4 kernel_size = None if not conv2d else mat.size()[2:4] conv2d_3x3 = conv2d and kernel_size != (1, 1) out_dim, in_dim = mat.size()[0:2] if conv2d: if conv2d_3x3: mat = mat.flatten(start_dim=1) else: mat = mat.squeeze() module_new_rank = new_conv_rank if conv2d_3x3 else new_rank module_new_rank = min(module_new_rank, in_dim, out_dim) # LoRA rank cannot exceed the original dim U, S, Vh = torch.linalg.svd(mat) U = U[:, :module_new_rank] S = S[:module_new_rank] U = U @ torch.diag(S) Vh = Vh[:module_new_rank, :] dist = torch.cat([U.flatten(), Vh.flatten()]) hi_val = torch.quantile(dist, CLAMP_QUANTILE) low_val = -hi_val U = U.clamp(low_val, hi_val) Vh = Vh.clamp(low_val, hi_val) if conv2d: U = U.reshape(out_dim, module_new_rank, 1, 1) Vh = Vh.reshape(module_new_rank, in_dim, kernel_size[0], kernel_size[1]) up_weight = U down_weight = Vh merged_lora_sd[lora_module_name + ".lora_up.weight"] = up_weight.to("cpu").contiguous() merged_lora_sd[lora_module_name + ".lora_down.weight"] = down_weight.to("cpu").contiguous() merged_lora_sd[lora_module_name + ".alpha"] = torch.tensor(module_new_rank) # build minimum metadata dims = f"{new_rank}" alphas = f"{new_rank}" if new_conv_rank is not None: network_args = {"conv_dim": new_conv_rank, "conv_alpha": new_conv_rank} else: network_args = None metadata = train_util.build_minimum_network_metadata(v2, base_model, "networks.lora", dims, alphas, network_args) return merged_lora_sd, metadata, v2 == "True", base_model def merge(args): assert len(args.models) == len(args.ratios), f"number of models must be equal to number of ratios / モデルの数と重みの数は合わせてください" def str_to_dtype(p): if p == "float": return torch.float if p == "fp16": return torch.float16 if p == "bf16": return torch.bfloat16 return None merge_dtype = str_to_dtype(args.precision) save_dtype = str_to_dtype(args.save_precision) if save_dtype is None: save_dtype = merge_dtype new_conv_rank = args.new_conv_rank if args.new_conv_rank is not None else args.new_rank state_dict, metadata, v2, base_model = merge_lora_models( args.models, args.ratios, args.new_rank, new_conv_rank, args.device, merge_dtype ) print(f"calculating hashes and creating metadata...") model_hash, legacy_hash = train_util.precalculate_safetensors_hashes(state_dict, metadata) metadata["sshs_model_hash"] = model_hash metadata["sshs_legacy_hash"] = legacy_hash if not args.no_metadata: is_sdxl = base_model is not None and base_model.lower().startswith("sdxl") merged_from = sai_model_spec.build_merged_from(args.models) title = os.path.splitext(os.path.basename(args.save_to))[0] sai_metadata = sai_model_spec.build_metadata( state_dict, v2, v2, is_sdxl, True, False, time.time(), title=title, merged_from=merged_from ) if v2: # TODO read sai modelspec print( "Cannot determine if LoRA is for v-prediction, so save metadata as v-prediction / LoRAがv-prediction用か否か不明なため、仮にv-prediction用としてmetadataを保存します" ) metadata.update(sai_metadata) print(f"saving model to: {args.save_to}") save_to_file(args.save_to, state_dict, save_dtype, metadata) def setup_parser() -> argparse.ArgumentParser: parser = argparse.ArgumentParser() parser.add_argument( "--save_precision", type=str, default=None, choices=[None, "float", "fp16", "bf16"], help="precision in saving, same to merging if omitted / 保存時に精度を変更して保存する、省略時はマージ時の精度と同じ", ) parser.add_argument( "--precision", type=str, default="float", choices=["float", "fp16", "bf16"], help="precision in merging (float is recommended) / マージの計算時の精度（floatを推奨）", ) parser.add_argument( "--save_to", type=str, default=None, help="destination file name: ckpt or safetensors file / 保存先のファイル名、ckptまたはsafetensors" ) parser.add_argument( "--models", type=str, nargs="*", help="LoRA models to merge: ckpt or safetensors file / マージするLoRAモデル、ckptまたはsafetensors" ) parser.add_argument("--ratios", type=float, nargs="*", help="ratios for each model / それぞれのLoRAモデルの比率") parser.add_argument("--new_rank", type=int, default=4, help="Specify rank of output LoRA / 出力するLoRAのrank (dim)") parser.add_argument( "--new_conv_rank", type=int, default=None, help="Specify rank of output LoRA for Conv2d 3x3, None for same as new_rank / 出力するConv2D 3x3 LoRAのrank (dim)、Noneでnew_rankと同じ", ) parser.add_argument("--device", type=str, default=None, help="device to use, cuda for GPU / 計算を行うデバイス、cuda でGPUを使う") parser.add_argument( "--no_metadata", action="store_true", help="do not save sai modelspec metadata (minimum ss_metadata for LoRA is saved) / " + "sai modelspecのメタデータを保存しない（LoRAの最低限のss_metadataは保存される）", ) return parser if __name__ == "__main__": parser = setup_parser() args = parser.parse_args() merge(args)