Update high-level api

This commit is contained in:
Andrei Betlen 2023-04-01 13:01:27 -04:00
parent 3af274cbd4
commit 318eae237e

View file

@ -2,10 +2,11 @@ import os
import uuid
import time
import multiprocessing
from typing import List, Optional
from typing import List, Optional, Union, Generator, Sequence
from collections import deque
from . import llama_cpp
from .llama_types import *
class Llama:
@ -14,7 +15,7 @@ class Llama:
def __init__(
self,
model_path: str,
# NOTE: The following parameters are likely to change in the future.
# NOTE: These parameters are likely to change in the future.
n_ctx: int = 512,
n_parts: int = -1,
seed: int = 1337,
@ -24,7 +25,9 @@ class Llama:
use_mlock: bool = False,
embedding: bool = False,
n_threads: Optional[int] = None,
) -> "Llama":
n_batch: int = 8,
last_n_tokens_size: int = 64,
):
"""Load a llama.cpp model from `model_path`.
Args:
@ -38,6 +41,8 @@ class Llama:
use_mlock: Force the system to keep the model in RAM.
embedding: Embedding mode only.
n_threads: Number of threads to use. If None, the number of threads is automatically determined.
n_batch: Maximum number of prompt tokens to batch together when calling llama_eval.
last_n_tokens_size: Maximum number of tokens to keep in the last_n_tokens deque.
Raises:
ValueError: If the model path does not exist.
@ -57,8 +62,8 @@ class Llama:
self.params.use_mlock = use_mlock
self.params.embedding = embedding
self.last_n = 64
self.max_chunk_size = n_ctx
self.last_n_tokens_size = last_n_tokens_size
self.n_batch = n_batch
self.n_threads = n_threads or multiprocessing.cpu_count()
@ -69,29 +74,33 @@ class Llama:
self.model_path.encode("utf-8"), self.params
)
def tokenize(self, text: bytes) -> List[int]:
def tokenize(self, text: bytes) -> List[llama_cpp.llama_token]:
"""Tokenize a string.
Args:
text: The utf-8 encoded string to tokenize.
Raises:
RuntimeError: If the tokenization failed.
Returns:
A list of tokens.
"""
assert self.ctx is not None
n_ctx = llama_cpp.llama_n_ctx(self.ctx)
tokens = (llama_cpp.llama_token * n_ctx)()
tokens = (llama_cpp.llama_token * int(n_ctx))()
n_tokens = llama_cpp.llama_tokenize(
self.ctx,
text,
tokens,
n_ctx,
True,
llama_cpp.c_bool(True),
)
if n_tokens < 0:
if int(n_tokens) < 0:
raise RuntimeError(f'Failed to tokenize: text="{text}" n_tokens={n_tokens}')
return list(tokens[:n_tokens])
def detokenize(self, tokens: List[int]) -> bytes:
def detokenize(self, tokens: List[llama_cpp.llama_token]) -> bytes:
"""Detokenize a list of tokens.
Args:
@ -100,62 +109,98 @@ class Llama:
Returns:
The detokenized string.
"""
assert self.ctx is not None
output = b""
for token in tokens:
output += llama_cpp.llama_token_to_str(self.ctx, token)
return output
def embed(self, text: str):
def generate(
self,
tokens: Sequence[llama_cpp.llama_token],
top_k: int,
top_p: float,
temp: float,
repeat_penalty: float,
) -> Generator[
llama_cpp.llama_token, Optional[Sequence[llama_cpp.llama_token]], None
]:
# Temporary workaround for https://github.com/ggerganov/llama.cpp/issues/684
if temp == 0.0:
temp = 1.0
top_p = 0.0
top_k = 1
assert self.ctx is not None
n_ctx = int(llama_cpp.llama_n_ctx(self.ctx))
n_tokens = 0
last_n_tokens = deque(
[llama_cpp.llama_token(0)] * self.last_n_tokens_size,
maxlen=self.last_n_tokens_size,
)
while True:
for i in range(0, len(tokens), self.n_batch):
batch = tokens[i : min(len(tokens), i + self.n_batch)]
n_past = min(n_ctx - len(batch), n_tokens)
return_code = llama_cpp.llama_eval(
ctx=self.ctx,
tokens=(llama_cpp.llama_token * len(batch))(*batch),
n_tokens=llama_cpp.c_int(len(batch)),
n_past=llama_cpp.c_int(n_past),
n_threads=llama_cpp.c_int(self.n_threads),
)
if int(return_code) != 0:
raise RuntimeError(f"llama_eval returned {return_code}")
last_n_tokens.extend(batch)
n_tokens += len(batch)
token = llama_cpp.llama_sample_top_p_top_k(
ctx=self.ctx,
last_n_tokens_data=(llama_cpp.llama_token * self.last_n_tokens_size)(
*last_n_tokens
),
last_n_tokens_size=llama_cpp.c_int(self.last_n_tokens_size),
top_k=llama_cpp.c_int(top_k),
top_p=llama_cpp.c_float(top_p),
temp=llama_cpp.c_float(temp),
repeat_penalty=llama_cpp.c_float(repeat_penalty),
)
tokens_or_none = yield token
tokens = [token]
if tokens_or_none is not None:
tokens.extend(tokens_or_none)
def create_embedding(self, input: str) -> Embedding:
"""Embed a string.
Args:
text: The utf-8 encoded string to embed.
input: The utf-8 encoded string to embed.
Returns:
A list of embeddings.
An embedding object.
"""
tokens = self.tokenize(text.encode("utf-8"))
self._eval(tokens, 0)
embeddings = llama_cpp.llama_get_embeddings(self.ctx)
return embeddings[:llama_cpp.llama_n_embd(self.ctx)]
assert self.ctx is not None
tokens = self.tokenize(input.encode("utf-8"))
next(self.generate(tokens, top_k=0, top_p=0.0, temp=1.0, repeat_penalty=1.0))
n_tokens = len(tokens)
embedding = llama_cpp.llama_get_embeddings(self.ctx)[
: llama_cpp.llama_n_embd(self.ctx)
]
return {
"object": "list",
"data": [
{
"object": "embedding",
"embedding": embedding,
"index": 0,
}
],
"model": self.model_path,
"usage": {
"prompt_tokens": n_tokens,
"total_tokens": n_tokens,
},
}
def _eval(self, tokens: List[int], n_past):
rc = llama_cpp.llama_eval(
self.ctx,
(llama_cpp.llama_token * len(tokens))(*tokens),
len(tokens),
n_past,
self.n_threads,
)
if rc != 0:
raise RuntimeError(f"Failed to evaluate: {rc}")
def _sample(self, last_n_tokens, top_p, top_k, temp, repeat_penalty):
return llama_cpp.llama_sample_top_p_top_k(
self.ctx,
(llama_cpp.llama_token * len(last_n_tokens))(*last_n_tokens),
len(last_n_tokens),
top_k=top_k,
top_p=top_p,
temp=temp,
repeat_penalty=repeat_penalty,
)
def _generate(self, past_tokens, max_tokens, top_p, top_k, temp, repeat_penalty):
last_n_tokens = deque([0] * self.last_n, maxlen=self.last_n)
last_n_tokens.extend(past_tokens)
for i in range(max_tokens):
token = self._sample(
last_n_tokens,
top_p=top_p,
top_k=top_k,
temp=temp,
repeat_penalty=repeat_penalty,
)
yield token
self._eval([token], len(past_tokens) + i)
def _call(
def _create_completion(
self,
prompt: str,
suffix: Optional[str] = None,
@ -168,28 +213,35 @@ class Llama:
repeat_penalty: float = 1.1,
top_k: int = 40,
stream: bool = False,
):
) -> Union[
Generator[Completion, None, None],
Generator[CompletionChunk, None, None],
]:
assert self.ctx is not None
completion_id = f"cmpl-{str(uuid.uuid4())}"
created = int(time.time())
completion_tokens = []
prompt_tokens = self.tokenize(prompt.encode("utf-8"))
completion_tokens: List[llama_cpp.llama_token] = []
# Add blank space to start of prompt to match OG llama tokenizer
prompt_tokens = self.tokenize(b" " + prompt.encode("utf-8"))
text = b""
if len(prompt_tokens) + max_tokens > llama_cpp.llama_n_ctx(self.ctx):
if len(prompt_tokens) + max_tokens > int(llama_cpp.llama_n_ctx(self.ctx)):
raise ValueError(
f"Requested tokens exceed context window of {llama_cpp.llama_n_ctx(self.ctx)}"
)
# Process prompt in chunks to avoid running out of memory
for i in range(0, len(prompt_tokens), self.max_chunk_size):
chunk = prompt_tokens[i : min(len(prompt_tokens), i + self.max_chunk_size)]
self._eval(chunk, n_past=i)
if stop is not None:
stop = [s.encode("utf-8") for s in stop]
if stop != []:
stop_bytes = [s.encode("utf-8") for s in stop]
else:
stop_bytes = []
finish_reason = None
for token in self._generate(
prompt_tokens, max_tokens, top_p, top_k, temperature, repeat_penalty
for token in self.generate(
prompt_tokens,
top_k=top_k,
top_p=top_p,
temp=temperature,
repeat_penalty=repeat_penalty,
):
if token == llama_cpp.llama_token_eos():
finish_reason = "stop"
@ -197,7 +249,7 @@ class Llama:
completion_tokens.append(token)
text = self.detokenize(completion_tokens)
any_stop = [s for s in stop if s in text]
any_stop = [s for s in stop_bytes if s in text]
if len(any_stop) > 0:
first_stop = any_stop[0]
text = text[: text.index(first_stop)]
@ -207,7 +259,8 @@ class Llama:
if stream:
start = len(self.detokenize(completion_tokens[:-1]))
longest = 0
for s in stop:
# TODO: Clean up this mess
for s in stop_bytes:
for i in range(len(s), 0, -1):
if s[-i:] == text[-i:]:
if i > longest:
@ -262,9 +315,7 @@ class Llama:
text = text + suffix
if logprobs is not None:
logprobs = llama_cpp.llama_get_logits(
self.ctx,
)[:logprobs]
raise NotImplementedError("logprobs not implemented")
yield {
"id": completion_id,
@ -275,7 +326,7 @@ class Llama:
{
"text": text,
"index": 0,
"logprobs": logprobs,
"logprobs": None,
"finish_reason": finish_reason,
}
],
@ -286,11 +337,66 @@ class Llama:
},
}
def create_completion(
self,
prompt: str,
suffix: Optional[str] = None,
max_tokens: int = 128,
temperature: float = 0.8,
top_p: float = 0.95,
logprobs: Optional[int] = None,
echo: bool = False,
stop: List[str] = [],
repeat_penalty: float = 1.1,
top_k: int = 40,
stream: bool = False,
) -> Union[Completion, Generator[CompletionChunk, None, None]]:
"""Generate text from a prompt.
Args:
prompt: The prompt to generate text from.
suffix: A suffix to append to the generated text. If None, no suffix is appended.
max_tokens: The maximum number of tokens to generate.
temperature: The temperature to use for sampling.
top_p: The top-p value to use for sampling.
logprobs: The number of logprobs to return. If None, no logprobs are returned.
echo: Whether to echo the prompt.
stop: A list of strings to stop generation when encountered.
repeat_penalty: The penalty to apply to repeated tokens.
top_k: The top-k value to use for sampling.
stream: Whether to stream the results.
Raises:
ValueError: If the requested tokens exceed the context window.
RuntimeError: If the prompt fails to tokenize or the model fails to evaluate the prompt.
Returns:
Response object containing the generated text.
"""
completion_or_chunks = self._create_completion(
prompt=prompt,
suffix=suffix,
max_tokens=max_tokens,
temperature=temperature,
top_p=top_p,
logprobs=logprobs,
echo=echo,
stop=stop,
repeat_penalty=repeat_penalty,
top_k=top_k,
stream=stream,
)
if stream:
chunks: Generator[CompletionChunk, None, None] = completion_or_chunks
return chunks
completion: Completion = next(completion_or_chunks) # type: ignore
return completion
def __call__(
self,
prompt: str,
suffix: Optional[str] = None,
max_tokens: int = 16,
max_tokens: int = 128,
temperature: float = 0.8,
top_p: float = 0.95,
logprobs: Optional[int] = None,
@ -322,7 +428,7 @@ class Llama:
Returns:
Response object containing the generated text.
"""
call = self._call(
return self.create_completion(
prompt=prompt,
suffix=suffix,
max_tokens=max_tokens,
@ -335,9 +441,8 @@ class Llama:
top_k=top_k,
stream=stream,
)
if stream:
return call
return next(call)
def __del__(self):
llama_cpp.llama_free(self.ctx)
if self.ctx is not None:
llama_cpp.llama_free(self.ctx)
self.ctx = None