mlx-examples/llms/mlx_lm/gguf.py
Anchen fe96ef342f
feat(mlx-lm): export the GGUF (fp16) format model weights from fuse.py (#555)
* wip

* wip

* feat: convert mlx model to gguf f16

* chore: conver norm layer to float32 to avoid overflow issue

* chore: add support for mixtral

* chore: clean up

* chore: remove unused import statement

* chore: clean up weight name mapping

* version and readme

* actual version bump

---------

Co-authored-by: Awni Hannun <awni@apple.com>
2024-03-21 10:34:11 -07:00

312 lines
11 KiB
Python

import re
from enum import IntEnum
from pathlib import Path
from typing import Iterable, Union
import mlx.core as mx
from transformers import AutoTokenizer
class TokenType(IntEnum):
NORMAL = 1
UNKNOWN = 2
CONTROL = 3
USER_DEFINED = 4
UNUSED = 5
BYTE = 6
class GGMLFileType(IntEnum):
GGML_TYPE_F16 = 1
# copied from https://github.com/ggerganov/llama.cpp/blob/master/convert.py#L455
class HfVocab:
def __init__(
self, fname_tokenizer: Path, fname_added_tokens: Path | None = None
) -> None:
self.tokenizer = AutoTokenizer.from_pretrained(
fname_tokenizer,
cache_dir=fname_tokenizer,
local_files_only=True,
)
self.added_tokens_list = []
self.added_tokens_dict = dict()
self.added_tokens_ids = set()
for tok, tokidx in sorted(
self.tokenizer.get_added_vocab().items(), key=lambda x: x[1]
):
if tokidx >= self.tokenizer.vocab_size:
self.added_tokens_list.append(tok)
self.added_tokens_dict[tok] = tokidx
self.added_tokens_ids.add(tokidx)
self.specials = {
tok: self.tokenizer.get_vocab()[tok]
for tok in self.tokenizer.all_special_tokens
}
self.special_ids = set(self.tokenizer.all_special_ids)
self.vocab_size_base = self.tokenizer.vocab_size
self.vocab_size = self.vocab_size_base + len(self.added_tokens_list)
self.fname_tokenizer = fname_tokenizer
self.fname_added_tokens = fname_added_tokens
def hf_tokens(self) -> Iterable[tuple[bytes, float, TokenType]]:
reverse_vocab = {
id: encoded_tok for encoded_tok, id in self.tokenizer.get_vocab().items()
}
for token_id in range(self.vocab_size_base):
if token_id in self.added_tokens_ids:
continue
token_text = reverse_vocab[token_id].encode("utf-8")
yield token_text, self.get_token_score(token_id), self.get_token_type(
token_id, token_text, self.special_ids
)
def get_token_type(
self, token_id: int, token_text: bytes, special_ids: set[int]
) -> TokenType:
if re.fullmatch(rb"<0x[0-9A-Fa-f]{2}>", token_text):
return TokenType.BYTE
return TokenType.CONTROL if token_id in special_ids else TokenType.NORMAL
def get_token_score(self, token_id: int) -> float:
return -1000.0
def added_tokens(self) -> Iterable[tuple[bytes, float, TokenType]]:
for text in self.added_tokens_list:
if text in self.specials:
toktype = self.get_token_type(
self.specials[text], b"", self.special_ids
)
score = self.get_token_score(self.specials[text])
else:
toktype = TokenType.USER_DEFINED
score = -1000.0
yield text.encode("utf-8"), score, toktype
def has_newline_token(self):
return "<0x0A>" in self.tokenizer.vocab or "\n" in self.tokenizer.vocab
def all_tokens(self) -> Iterable[tuple[bytes, float, TokenType]]:
yield from self.hf_tokens()
yield from self.added_tokens()
def __repr__(self) -> str:
return f"<HfVocab with {self.vocab_size_base} base tokens and {len(self.added_tokens_list)} added tokens>"
@staticmethod
def load(path: Path) -> "HfVocab":
added_tokens_path = path.parent / "added_tokens.json"
return HfVocab(path, added_tokens_path if added_tokens_path.exists() else None)
def translate_weight_names(name):
name = name.replace("model.layers.", "blk.")
# for mixtral gate
name = name.replace("block_sparse_moe.gate", "ffn_gate_inp")
# for mixtral experts ffns
pattern = r"block_sparse_moe\.experts\.(\d+)\.w1\.weight"
replacement = r"ffn_gate.\1.weight"
name = re.sub(pattern, replacement, name)
pattern = r"block_sparse_moe\.experts\.(\d+)\.w2\.weight"
replacement = r"ffn_down.\1.weight"
name = re.sub(pattern, replacement, name)
pattern = r"block_sparse_moe\.experts\.(\d+)\.w3\.weight"
replacement = r"ffn_up.\1.weight"
name = re.sub(pattern, replacement, name)
name = name.replace("mlp.gate_proj", "ffn_gate")
name = name.replace("mlp.down_proj", "ffn_down")
name = name.replace("mlp.up_proj", "ffn_up")
name = name.replace("self_attn.q_proj", "attn_q")
name = name.replace("self_attn.k_proj", "attn_k")
name = name.replace("self_attn.v_proj", "attn_v")
name = name.replace("self_attn.o_proj", "attn_output")
name = name.replace("input_layernorm", "attn_norm")
name = name.replace("post_attention_layernorm", "ffn_norm")
name = name.replace("model.embed_tokens", "token_embd")
name = name.replace("model.norm", "output_norm")
name = name.replace("lm_head", "output")
return name
def permute_weights(weights, n_head, n_head_kv=None):
if n_head_kv is not None and n_head != n_head_kv:
n_head = n_head_kv
reshaped = weights.reshape(
n_head, 2, weights.shape[0] // n_head // 2, *weights.shape[1:]
)
swapped = reshaped.swapaxes(1, 2)
final_shape = weights.shape
return swapped.reshape(final_shape)
def prepare_metadata(config, vocab):
metadata = {
"general.name": "llama",
"llama.context_length": (
mx.array(config["max_position_embeddings"], dtype=mx.uint32)
if config.get("max_position_embeddings") is not None
else None
),
"llama.embedding_length": (
mx.array(config["hidden_size"], dtype=mx.uint32)
if config.get("hidden_size") is not None
else None
),
"llama.block_count": (
mx.array(config["num_hidden_layers"], dtype=mx.uint32)
if config.get("num_hidden_layers") is not None
else None
),
"llama.feed_forward_length": (
mx.array(config["intermediate_size"], dtype=mx.uint32)
if config.get("intermediate_size") is not None
else None
),
"llama.rope.dimension_count": (
mx.array(
config["hidden_size"] // config["num_attention_heads"], dtype=mx.uint32
)
if config.get("hidden_size") is not None
and config.get("num_attention_heads") is not None
else None
),
"llama.attention.head_count": (
mx.array(config["num_attention_heads"], dtype=mx.uint32)
if config.get("num_attention_heads") is not None
else None
),
"llama.attention.head_count_kv": (
mx.array(
config.get("num_key_value_heads", config["num_attention_heads"]),
dtype=mx.uint32,
)
if config.get("num_attention_heads") is not None
else None
),
"llama.expert_count": (
mx.array(config.get("num_local_experts", None), dtype=mx.uint32)
if config.get("num_local_experts") is not None
else None
),
"llama.expert_used_count": (
mx.array(config.get("num_experts_per_tok", None), dtype=mx.uint32)
if config.get("num_experts_per_tok") is not None
else None
),
"llama.attention.layer_norm_rms_epsilon": (
mx.array(config.get("rms_norm_eps", 1e-05))
if config.get("rms_norm_eps") is not None
else None
),
"llama.rope.freq_base": (
mx.array(config.get("rope_theta", 10000), dtype=mx.float32)
if config.get("rope_theta") is not None
else None
),
}
rope_scaling = config.get("rope_scaling")
if rope_scaling is not None and (typ := rope_scaling.get("type")):
rope_factor = rope_scaling.get("factor")
f_rope_scale = rope_factor
if typ == "linear":
rope_scaling_type = "linear"
metadata["llama.rope.scaling.type"] = rope_scaling_type
metadata["llama.rope.scaling.factor"] = mx.array(f_rope_scale)
metadata["general.file_type"] = mx.array(
GGMLFileType.GGML_TYPE_F16.value,
dtype=mx.uint32,
)
metadata["general.quantization_version"] = mx.array(
GGMLFileType.GGML_TYPE_F16.value,
dtype=mx.uint32,
)
metadata["general.name"] = config.get("_name_or_path", "llama").split("/")[-1]
metadata["general.architecture"] = "llama"
metadata["general.alignment"] = mx.array(32, dtype=mx.uint32)
# add metadata for vocab
metadata["tokenizer.ggml.model"] = "llama"
tokens = []
scores = []
toktypes = []
for text, score, toktype in vocab.all_tokens():
tokens.append(text)
scores.append(score)
toktypes.append(toktype.value)
assert len(tokens) == vocab.vocab_size
metadata["tokenizer.ggml.tokens"] = tokens
metadata["tokenizer.ggml.scores"] = mx.array(scores, dtype=mx.float32)
metadata["tokenizer.ggml.token_type"] = mx.array(toktypes, dtype=mx.uint32)
metadata["tokenizer.ggml.bos_token_id"] = mx.array(
vocab.tokenizer.bos_token_id, dtype=mx.uint32
)
metadata["tokenizer.ggml.eos_token_id"] = mx.array(
vocab.tokenizer.eos_token_id, dtype=mx.uint32
)
metadata["tokenizer.ggml.unknown_token_id"] = mx.array(
vocab.tokenizer.unk_token_id, dtype=mx.uint32
)
metadata = {k: v for k, v in metadata.items() if v is not None}
return metadata
def convert_to_gguf(
model_path: Union[str, Path],
weights: dict,
config: dict,
output_file_path: str,
):
if isinstance(model_path, str):
model_path = Path(model_path)
quantization = config.get("quantization", None)
if quantization:
raise NotImplementedError(
"Conversion of quantized models is not yet supported."
)
print("Converting to GGUF format")
# https://github.com/ggerganov/llama.cpp/blob/master/convert.py#L1182 seems relate to llama.cpp's multihead attention
weights = {
k: (
permute_weights(
v, config["num_attention_heads"], config["num_attention_heads"]
)
if "self_attn.q_proj.weight" in k
else (
permute_weights(
v, config["num_attention_heads"], config["num_key_value_heads"]
)
if "self_attn.k_proj.weight" in k
else v
)
)
for k, v in weights.items()
}
# rename weights for gguf format
weights = {translate_weight_names(k): v for k, v in weights.items()}
if not (model_path / "tokenizer.json").exists():
raise ValueError("Tokenizer json not found")
vocab = HfVocab.load(model_path)
metadata = prepare_metadata(config, vocab)
weights = {
k: (
v.astype(mx.float32).astype(mx.float16)
if v.dtype == mx.bfloat16
else v.astype(mx.float32) if "norm" in k else v
)
for k, v in weights.items()
}
output_file_path = output_file_path
mx.save_gguf(output_file_path, weights, metadata)
print(f"Converted GGUF model saved as: {output_file_path}")