mirror of
https://github.com/hiyouga/LLaMA-Factory.git
synced 2025-08-04 12:42:51 +08:00
add noisy mean initialization #1815
Former-commit-id: a66186b8724ffd0351a32593ab52d8a2312f339b
This commit is contained in:
parent
4e75ca1222
commit
7c362509a6
@ -1,3 +1,4 @@
|
||||
import math
|
||||
import torch
|
||||
from typing import TYPE_CHECKING, Any, Dict, List, Optional, Set, Tuple
|
||||
|
||||
@ -124,6 +125,14 @@ def load_valuehead_params(model_args: "ModelArguments") -> Dict[str, torch.Tenso
|
||||
return None
|
||||
|
||||
|
||||
def noisy_mean_initialization(embed_weight: torch.Tensor, num_new_tokens: int):
|
||||
embedding_dim = embed_weight.size(1)
|
||||
avg_weight = embed_weight[:-num_new_tokens].mean(dim=0, keepdim=True)
|
||||
noise_weight = torch.empty_like(avg_weight[-num_new_tokens:])
|
||||
noise_weight.normal_(mean=0, std=(1.0 / math.sqrt(embedding_dim)))
|
||||
embed_weight[-num_new_tokens:] = avg_weight + noise_weight
|
||||
|
||||
|
||||
def prepare_model_for_training(
|
||||
model: "PreTrainedModel",
|
||||
finetuning_args: "FinetuningArguments",
|
||||
@ -181,6 +190,10 @@ def resize_embedding_layer(model: "PreTrainedModel", tokenizer: "PreTrainedToken
|
||||
|
||||
model.resize_token_embeddings(len(tokenizer), pad_to_multiple_of=64)
|
||||
new_embedding_size = model.get_input_embeddings().weight.size(0)
|
||||
num_new_tokens = new_embedding_size - current_embedding_size
|
||||
noisy_mean_initialization(model.get_input_embeddings().weight.data, num_new_tokens)
|
||||
noisy_mean_initialization(model.get_output_embeddings().weight.data, num_new_tokens)
|
||||
|
||||
logger.info("Resized token embeddings from {} to {}.".format(current_embedding_size, new_embedding_size))
|
||||
|
||||
|
||||
|
Loading…
x
Reference in New Issue
Block a user