# Copyright 2023 Mistral AI and The HuggingFace Inc. team. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import argparse
import gc
import json
import os
import shutil
import warnings
import torch
from safetensors.torch import load_file as safe_load_file
from transformers import (
LlamaTokenizer,
MistralConfig,
MistralForCausalLM,
AddedToken,
)
try:
from transformers import LlamaTokenizerFast
tokenizer_class = LlamaTokenizerFast
except ImportError as e:
warnings.warn(e)
warnings.warn(
"The converted tokenizer will be the `slow` tokenizer. To use the fast, update your `tokenizers` library and re-run the tokenizer conversion"
)
tokenizer_class = LlamaTokenizer
"""
Sample usage:
```
python src/transformers/models/mistral/convert_mistral_weights_to_hf.py \
--input_dir /path/to/downloaded/mistral/weights --model_size 22B --output_dir /output/path
```
Thereafter, models can be loaded via:
```py
from transformers import MistralForCausalLM, LlamaTokenizer
model = MistralForCausalLM.from_pretrained("/output/path")
tokenizer = LlamaTokenizer.from_pretrained("/output/path")
```
Important note: you need to be able to host the whole model in RAM to execute this script (even if the biggest versions
come in several checkpoints they each contain a part of each weight of the model, so we need to load them all in RAM).
"""
NUM_SHARDS = {"22B": 1}
def compute_intermediate_size(n, ffn_dim_multiplier=1, multiple_of=256):
return multiple_of * ((int(ffn_dim_multiplier * int(8 * n / 3)) + multiple_of - 1) // multiple_of)
def read_json(path):
with open(path, "r") as f:
return json.load(f)
def write_json(text, path):
with open(path, "w") as f:
json.dump(text, f)
def write_model(model_path, input_base_path, model_size, tokenizer_path=None, safe_serialization=True, is_v3=False):
# for backward compatibility, before you needed the repo to be called `my_repo/model_size`
if not os.path.isfile(os.path.join(input_base_path, "params.json")):
input_base_path = os.path.join(input_base_path, model_size)
os.makedirs(model_path, exist_ok=True)
tmp_model_path = os.path.join(model_path, "tmp")
os.makedirs(tmp_model_path, exist_ok=True)
params = read_json(os.path.join(input_base_path, "params.json"))
num_shards = NUM_SHARDS[model_size]
sliding_window = params.get("sliding_window", None)
# For some reason this is a string in the params.json
if sliding_window is not None:
sliding_window = int(sliding_window)
n_layers = params["n_layers"]
n_heads = params["n_heads"]
n_heads_per_shard = n_heads // num_shards
dim = params["dim"]
dims_per_head = dim // n_heads
base = params.get("rope_theta", 10000.0)
inv_freq = 1.0 / (base ** (torch.arange(0, dims_per_head, 2).float() / dims_per_head))
max_position_embeddings = 4096 * 8
if tokenizer_path is not None:
tokenizer = write_tokenizer(model_path, tokenizer_path + ".v3" if is_v3 else "")
vocab_size = tokenizer.vocab_size if tokenizer_path is not None else 32000
if "n_kv_heads" in params:
num_key_value_heads = params["n_kv_heads"] # for GQA / MQA
num_local_key_value_heads = num_key_value_heads // num_shards
key_value_dim = dims_per_head * num_local_key_value_heads
else: # compatibility with other checkpoints
num_key_value_heads = n_heads
num_local_key_value_heads = n_heads_per_shard
key_value_dim = dim
# permute for sliced rotary
def permute(w, n_heads=n_heads, dim1=dim, dim2=dim):
return w.view(n_heads, dim1 // n_heads // 2, 2, dim2).transpose(1, 2).reshape(dim1, dim2)
print(f"Fetching all parameters from the checkpoint at {input_base_path}.")
# Load weights - for v3 models the consolidated weights are in a single file format in safetensors
if is_v3:
loaded = [safe_load_file(os.path.join(input_base_path, "consolidated.safetensors"))]
else:
loaded = [
torch.load(os.path.join(input_base_path, f"consolidated.{i:02d}.pth"), map_location="cpu")
for i in range(num_shards)
]
param_count = 0
index_dict = {"weight_map": {}}
for layer_i in range(n_layers):
filename = f"pytorch_model-{layer_i + 1}-of-{n_layers + 1}.bin"
# Sharded
# Note that attention.w{q,k,v,o}, feed_fordward.w[1,2,3], attention_norm.weight and ffn_norm.weight share
# the same storage object, saving attention_norm and ffn_norm will save other weights too, which is
# redundant as other weights will be stitched from multiple shards. To avoid that, they are cloned.
state_dict = {
f"model.layers.{layer_i}.input_layernorm.weight": loaded[0][
f"layers.{layer_i}.attention_norm.weight"
].clone(),
f"model.layers.{layer_i}.post_attention_layernorm.weight": loaded[0][
f"layers.{layer_i}.ffn_norm.weight"
].clone(),
}
state_dict[f"model.layers.{layer_i}.self_attn.q_proj.weight"] = permute(
torch.cat(
[
loaded[i][f"layers.{layer_i}.attention.wq.weight"].view(n_heads_per_shard, dims_per_head, dim)
for i in range(num_shards)
],
dim=0,
).reshape(dim, dim)
)
state_dict[f"model.layers.{layer_i}.self_attn.k_proj.weight"] = permute(
torch.cat(
[
loaded[i][f"layers.{layer_i}.attention.wk.weight"].view(
num_local_key_value_heads, dims_per_head, dim
)
for i in range(num_shards)
],
dim=0,
).reshape(key_value_dim, dim),
num_key_value_heads,
key_value_dim,
dim,
)
state_dict[f"model.layers.{layer_i}.self_attn.v_proj.weight"] = torch.cat(
[
loaded[i][f"layers.{layer_i}.attention.wv.weight"].view(num_local_key_value_heads, dims_per_head, dim)
for i in range(num_shards)
],
dim=0,
).reshape(key_value_dim, dim)
state_dict[f"model.layers.{layer_i}.self_attn.o_proj.weight"] = torch.cat(
[loaded[i][f"layers.{layer_i}.attention.wo.weight"] for i in range(num_shards)], dim=1
)
state_dict[f"model.layers.{layer_i}.mlp.gate_proj.weight"] = torch.cat(
[loaded[i][f"layers.{layer_i}.feed_forward.w1.weight"] for i in range(num_shards)], dim=0
)
state_dict[f"model.layers.{layer_i}.mlp.down_proj.weight"] = torch.cat(
[loaded[i][f"layers.{layer_i}.feed_forward.w2.weight"] for i in range(num_shards)], dim=1
)
state_dict[f"model.layers.{layer_i}.mlp.up_proj.weight"] = torch.cat(
[loaded[i][f"layers.{layer_i}.feed_forward.w3.weight"] for i in range(num_shards)], dim=0
)
state_dict[f"model.layers.{layer_i}.self_attn.rotary_emb.inv_freq"] = inv_freq
for k, v in state_dict.items():
index_dict["weight_map"][k] = filename
param_count += v.numel()
torch.save(state_dict, os.path.join(tmp_model_path, filename))
filename = f"pytorch_model-{n_layers + 1}-of-{n_layers + 1}.bin"
state_dict = {
"model.norm.weight": loaded[0]["norm.weight"],
"model.embed_tokens.weight": torch.cat([loaded[i]["tok_embeddings.weight"] for i in range(num_shards)], dim=1),
"lm_head.weight": torch.cat([loaded[i]["output.weight"] for i in range(num_shards)], dim=0),
}
for k, v in state_dict.items():
index_dict["weight_map"][k] = filename
param_count += v.numel()
torch.save(state_dict, os.path.join(tmp_model_path, filename))
# Write configs
index_dict["metadata"] = {"total_size": param_count * 2}
write_json(index_dict, os.path.join(tmp_model_path, "pytorch_model.bin.index.json"))
config = MistralConfig(
hidden_size=dim,
intermediate_size=params["hidden_dim"],
num_attention_heads=params["n_heads"],
num_hidden_layers=params["n_layers"],
rms_norm_eps=params["norm_eps"],
num_key_value_heads=num_key_value_heads,
vocab_size=vocab_size,
rope_theta=base,
max_position_embeddings=max_position_embeddings,
sliding_window=sliding_window,
)
config.save_pretrained(tmp_model_path)
# Make space so we can load the model properly now.
del state_dict
del loaded
gc.collect()
print("Loading the checkpoint in a Mistral model.")
model = MistralForCausalLM.from_pretrained(tmp_model_path, torch_dtype=torch.bfloat16, low_cpu_mem_usage=True)
# Avoid saving this as part of the config.
del model.config._name_or_path
model.config.torch_dtype = torch.float16
print("Saving in the Transformers format.")
model.save_pretrained(model_path, safe_serialization=safe_serialization)
shutil.rmtree(tmp_model_path)
def write_tokenizer(tokenizer_path, input_tokenizer_path):
# Initialize the tokenizer based on the `spm` model
print(f"Saving a {tokenizer_class.__name__} to {tokenizer_path}.")
tokenizer = tokenizer_class(input_tokenizer_path)
tokenizer.add_tokens([
AddedToken('[INST]', special=True),
AddedToken('[/INST]', special=True),
AddedToken('[PREFIX]', special=True),
AddedToken('[SUFFIX]', special=True),
AddedToken('[MIDDLE]', special=True),
AddedToken('[IMG]', special=True),
])
tokenizer.save_pretrained(tokenizer_path)
return tokenizer
def main():
parser = argparse.ArgumentParser()
parser.add_argument(
"--input_dir",
help="Location of Mistral weights, which contains tokenizer.model and model folders",
)
parser.add_argument(
"--model_size",
choices=["22B", "tokenizer_only"],
help="'f' models correspond to the finetuned versions, and are specific to the Mistral2 official release. For more details on Mistral2, checkout the original repo: https://huggingface.co/meta-mistral",
)
parser.add_argument(
"--output_dir",
help="Location to write HF model and tokenizer",
)
parser.add_argument("--safe_serialization", type=bool, help="Whether or not to save using `safetensors`.")
parser.add_argument(
"--is_v3", action="store_true", help="Whether the checkpoints correspond to the 3rd version or not."
)
args = parser.parse_args()
spm_path = os.path.join(args.input_dir, "tokenizer.model")
if args.model_size != "tokenizer_only":
write_model(
model_path=args.output_dir,
input_base_path=args.input_dir,
model_size=args.model_size,
safe_serialization=args.safe_serialization,
tokenizer_path=spm_path,
is_v3=args.is_v3,
)
else:
write_tokenizer(args.output_dir, spm_path)
if __name__ == "__main__":
main()