diff --git a/tools/resize_lora.py b/tools/resize_lora.py new file mode 100644 index 0000000..b99bb5b --- /dev/null +++ b/tools/resize_lora.py @@ -0,0 +1,339 @@ +# +# File from: https://raw.githubusercontent.com/mgz-dev/sd-scripts/main/networks/resize_lora.py +# + +# Convert LoRA to different rank approximation (should only be used to go to lower rank) +# This code is based off the extract_lora_from_models.py file which is based on https://github.com/cloneofsimo/lora/blob/develop/lora_diffusion/cli_svd.py +# Thanks to cloneofsimo and kohya + +import argparse +import torch +from safetensors.torch import load_file, save_file, safe_open +from tqdm import tqdm +from library import train_util, model_util +import numpy as np + +MIN_SV = 1e-6 + +def load_state_dict(file_name, dtype): + if model_util.is_safetensors(file_name): + sd = load_file(file_name) + with safe_open(file_name, framework="pt") as f: + metadata = f.metadata() + else: + sd = torch.load(file_name, map_location='cpu') + metadata = None + + 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, model, 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 model_util.is_safetensors(file_name): + save_file(model, file_name, metadata) + else: + torch.save(model, file_name) + + +def index_sv_cumulative(S, target): + original_sum = float(torch.sum(S)) + cumulative_sums = torch.cumsum(S, dim=0)/original_sum + index = int(torch.searchsorted(cumulative_sums, target)) + 1 + if index >= len(S): + index = len(S) - 1 + + return index + + +def index_sv_fro(S, target): + S_squared = S.pow(2) + s_fro_sq = float(torch.sum(S_squared)) + sum_S_squared = torch.cumsum(S_squared, dim=0)/s_fro_sq + index = int(torch.searchsorted(sum_S_squared, target**2)) + 1 + if index >= len(S): + index = len(S) - 1 + + return index + + +# Modified from Kohaku-blueleaf's extract/merge functions +def extract_conv(weight, lora_rank, dynamic_method, dynamic_param, device, scale=1): + out_size, in_size, kernel_size, _ = weight.size() + U, S, Vh = torch.linalg.svd(weight.reshape(out_size, -1).to(device)) + + param_dict = rank_resize(S, lora_rank, dynamic_method, dynamic_param, scale) + lora_rank = param_dict["new_rank"] + + U = U[:, :lora_rank] + S = S[:lora_rank] + U = U @ torch.diag(S) + Vh = Vh[:lora_rank, :] + + param_dict["lora_down"] = Vh.reshape(lora_rank, in_size, kernel_size, kernel_size).cpu() + param_dict["lora_up"] = U.reshape(out_size, lora_rank, 1, 1).cpu() + del U, S, Vh, weight + return param_dict + + +def extract_linear(weight, lora_rank, dynamic_method, dynamic_param, device, scale=1): + out_size, in_size = weight.size() + + U, S, Vh = torch.linalg.svd(weight.to(device)) + + param_dict = rank_resize(S, lora_rank, dynamic_method, dynamic_param, scale) + lora_rank = param_dict["new_rank"] + + U = U[:, :lora_rank] + S = S[:lora_rank] + U = U @ torch.diag(S) + Vh = Vh[:lora_rank, :] + + param_dict["lora_down"] = Vh.reshape(lora_rank, in_size).cpu() + param_dict["lora_up"] = U.reshape(out_size, lora_rank).cpu() + del U, S, Vh, weight + return param_dict + + +def merge_conv(lora_down, lora_up, device): + in_rank, in_size, kernel_size, k_ = lora_down.shape + out_size, out_rank, _, _ = lora_up.shape + assert in_rank == out_rank and kernel_size == k_, f"rank {in_rank} {out_rank} or kernel {kernel_size} {k_} mismatch" + + lora_down = lora_down.to(device) + lora_up = lora_up.to(device) + + merged = lora_up.reshape(out_size, -1) @ lora_down.reshape(in_rank, -1) + weight = merged.reshape(out_size, in_size, kernel_size, kernel_size) + del lora_up, lora_down + return weight + + +def merge_linear(lora_down, lora_up, device): + in_rank, in_size = lora_down.shape + out_size, out_rank = lora_up.shape + assert in_rank == out_rank, f"rank {in_rank} {out_rank} mismatch" + + lora_down = lora_down.to(device) + lora_up = lora_up.to(device) + + weight = lora_up @ lora_down + del lora_up, lora_down + return weight + + +def rank_resize(S, rank, dynamic_method, dynamic_param, scale=1): + param_dict = {} + + if dynamic_method=="sv_ratio": + # Calculate new dim and alpha based off ratio + max_sv = S[0] + min_sv = max_sv/dynamic_param + new_rank = max(torch.sum(S > min_sv).item(),1) + new_alpha = float(scale*new_rank) + + elif dynamic_method=="sv_cumulative": + # Calculate new dim and alpha based off cumulative sum + new_rank = index_sv_cumulative(S, dynamic_param) + new_rank = max(new_rank, 1) + new_alpha = float(scale*new_rank) + + elif dynamic_method=="sv_fro": + # Calculate new dim and alpha based off sqrt sum of squares + new_rank = index_sv_fro(S, dynamic_param) + new_rank = min(max(new_rank, 1), len(S)-1) + new_alpha = float(scale*new_rank) + else: + new_rank = rank + new_alpha = float(scale*new_rank) + + + if S[0] <= MIN_SV: # Zero matrix, set dim to 1 + new_rank = 1 + new_alpha = float(scale*new_rank) + elif new_rank > rank: # cap max rank at rank + new_rank = rank + new_alpha = float(scale*new_rank) + + + # Calculate resize info + s_sum = torch.sum(torch.abs(S)) + s_rank = torch.sum(torch.abs(S[:new_rank])) + + S_squared = S.pow(2) + s_fro = torch.sqrt(torch.sum(S_squared)) + s_red_fro = torch.sqrt(torch.sum(S_squared[:new_rank])) + fro_percent = float(s_red_fro/s_fro) + + param_dict["new_rank"] = new_rank + param_dict["new_alpha"] = new_alpha + param_dict["sum_retained"] = (s_rank)/s_sum + param_dict["fro_retained"] = fro_percent + param_dict["max_ratio"] = S[0]/S[new_rank] + + return param_dict + + +def resize_lora_model(lora_sd, new_rank, save_dtype, device, dynamic_method, dynamic_param, verbose): + network_alpha = None + network_dim = None + verbose_str = "\n" + fro_list = [] + + # Extract loaded lora dim and alpha + for key, value in lora_sd.items(): + if network_alpha is None and 'alpha' in key: + network_alpha = value + if network_dim is None and 'lora_down' in key and len(value.size()) == 2: + network_dim = value.size()[0] + if network_alpha is not None and network_dim is not None: + break + if network_alpha is None: + network_alpha = network_dim + + scale = network_alpha/network_dim + + if dynamic_method: + print(f"Dynamically determining new alphas and dims based off {dynamic_method}: {dynamic_param}, max rank is {new_rank}") + + lora_down_weight = None + lora_up_weight = None + + o_lora_sd = lora_sd.copy() + block_down_name = None + block_up_name = None + + with torch.no_grad(): + for key, value in tqdm(lora_sd.items()): + if 'lora_down' in key: + block_down_name = key.split(".")[0] + lora_down_weight = value + if 'lora_up' in key: + block_up_name = key.split(".")[0] + lora_up_weight = value + + weights_loaded = (lora_down_weight is not None and lora_up_weight is not None) + + if (block_down_name == block_up_name) and weights_loaded: + + conv2d = (len(lora_down_weight.size()) == 4) + + if conv2d: + full_weight_matrix = merge_conv(lora_down_weight, lora_up_weight, device) + param_dict = extract_conv(full_weight_matrix, new_rank, dynamic_method, dynamic_param, device, scale) + else: + full_weight_matrix = merge_linear(lora_down_weight, lora_up_weight, device) + param_dict = extract_linear(full_weight_matrix, new_rank, dynamic_method, dynamic_param, device, scale) + + if verbose: + max_ratio = param_dict['max_ratio'] + sum_retained = param_dict['sum_retained'] + fro_retained = param_dict['fro_retained'] + if not np.isnan(fro_retained): + fro_list.append(float(fro_retained)) + + verbose_str+=f"{block_down_name:75} | " + verbose_str+=f"sum(S) retained: {sum_retained:.1%}, fro retained: {fro_retained:.1%}, max(S) ratio: {max_ratio:0.1f}" + + if verbose and dynamic_method: + verbose_str+=f", dynamic | dim: {param_dict['new_rank']}, alpha: {param_dict['new_alpha']}\n" + else: + verbose_str+=f"\n" + + new_alpha = param_dict['new_alpha'] + o_lora_sd[block_down_name + "." + "lora_down.weight"] = param_dict["lora_down"].to(save_dtype).contiguous() + o_lora_sd[block_up_name + "." + "lora_up.weight"] = param_dict["lora_up"].to(save_dtype).contiguous() + o_lora_sd[block_up_name + "." "alpha"] = torch.tensor(param_dict['new_alpha']).to(save_dtype) + + block_down_name = None + block_up_name = None + lora_down_weight = None + lora_up_weight = None + weights_loaded = False + del param_dict + + if verbose: + print(verbose_str) + + print(f"Average Frobenius norm retention: {np.mean(fro_list):.2%} | std: {np.std(fro_list):0.3f}") + print("resizing complete") + return o_lora_sd, network_dim, new_alpha + + +def resize(args): + + 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 + + if args.dynamic_method and not args.dynamic_param: + raise Exception("If using dynamic_method, then dynamic_param is required") + + merge_dtype = str_to_dtype('float') # matmul method above only seems to work in float32 + save_dtype = str_to_dtype(args.save_precision) + if save_dtype is None: + save_dtype = merge_dtype + + print("loading Model...") + lora_sd, metadata = load_state_dict(args.model, merge_dtype) + + print("Resizing Lora...") + state_dict, old_dim, new_alpha = resize_lora_model(lora_sd, args.new_rank, save_dtype, args.device, args.dynamic_method, args.dynamic_param, args.verbose) + + # update metadata + if metadata is None: + metadata = {} + + comment = metadata.get("ss_training_comment", "") + + if not args.dynamic_method: + metadata["ss_training_comment"] = f"dimension is resized from {old_dim} to {args.new_rank}; {comment}" + metadata["ss_network_dim"] = str(args.new_rank) + metadata["ss_network_alpha"] = str(new_alpha) + else: + metadata["ss_training_comment"] = f"Dynamic resize with {args.dynamic_method}: {args.dynamic_param} from {old_dim}; {comment}" + metadata["ss_network_dim"] = 'Dynamic' + metadata["ss_network_alpha"] = 'Dynamic' + + model_hash, legacy_hash = train_util.precalculate_safetensors_hashes(state_dict, metadata) + metadata["sshs_model_hash"] = model_hash + metadata["sshs_legacy_hash"] = legacy_hash + + print(f"saving model to: {args.save_to}") + save_to_file(args.save_to, state_dict, state_dict, save_dtype, metadata) + + +if __name__ == '__main__': + parser = argparse.ArgumentParser() + + parser.add_argument("--save_precision", type=str, default=None, + choices=[None, "float", "fp16", "bf16"], help="precision in saving, float if omitted / 保存時の精度、未指定時はfloat") + 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("--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("--model", type=str, default=None, + help="LoRA model to resize at to new rank: ckpt or safetensors file / 読み込むLoRAモデル、ckptまたはsafetensors") + 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("--verbose", action="store_true", + help="Display verbose resizing information / rank変更時の詳細情報を出力する") + parser.add_argument("--dynamic_method", type=str, default=None, choices=[None, "sv_ratio", "sv_fro", "sv_cumulative"], + help="Specify dynamic resizing method, --new_rank is used as a hard limit for max rank") + parser.add_argument("--dynamic_param", type=float, default=None, + help="Specify target for dynamic reduction") + + + args = parser.parse_args() + resize(args) \ No newline at end of file