tabbyAPI-ollama/model.py
kingbri 126afdfdc2 Model: Fix gpu split params
GPU split auto is a bool and GPU split is an array of integers for
GBs to allocate per GPU.

Signed-off-by: kingbri <bdashore3@proton.me>
2023-11-15 00:55:15 -05:00

347 lines
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14 KiB
Python

import gc, time, pathlib
import torch
from exllamav2 import(
ExLlamaV2,
ExLlamaV2Config,
ExLlamaV2Cache,
ExLlamaV2Cache_8bit,
ExLlamaV2Tokenizer,
)
from exllamav2.generator import(
ExLlamaV2StreamingGenerator,
ExLlamaV2Sampler
)
from typing import List, Optional
# Bytes to reserve on first device when loading with auto split
auto_split_reserve_bytes = 96 * 1024**2
class ModelContainer:
config: Optional[ExLlamaV2Config] = None
draft_config: Optional[ExLlamaV2Config] = None
model: Optional[ExLlamaV2] = None
draft_model: Optional[ExLlamaV2] = None
cache: Optional[ExLlamaV2Cache] = None
draft_cache: Optional[ExLlamaV2Cache] = None
tokenizer: Optional[ExLlamaV2Tokenizer] = None
generator: Optional[ExLlamaV2StreamingGenerator] = None
cache_fp8: bool = False
draft_enabled: bool = False
gpu_split_auto: bool = True
gpu_split: list or None = None
def __init__(self, model_directory: pathlib.Path, quiet = False, **kwargs):
"""
Create model container
Args:
model_dir (int): Model directory containing config.json, tokenizer.model etc.
quiet (bool): Suppress console output
load_progress_callback (function, optional): A function to call for each module loaded. Prototype:
def progress(loaded_modules: int, total_modules: int, loading_draft: bool)
**kwargs:
`cache_mode` (str): Sets cache mode, "FP16" or "FP8" (defaulf: "FP16")
'max_seq_len' (int): Override model's default max sequence length
'rope_scale' (float): Set RoPE scaling factor for model (default: 1.0)
'rope_alpha' (float): Set RoPE alpha (NTK) factor for model (default: 1.0)
'chunk_size' (int): Sets the maximum chunk size for the model (default: 2048)
Inferencing in chunks reduces overall VRAM overhead by processing very long sequences in smaller
batches. This limits the size of temporary buffers needed for the hidden state and attention
weights.
'draft_model_dir' (str): Draft model directory
'draft_rope_alpha' (float): RoPE alpha (NTK) factor for draft model.
By default, the draft model's alpha value is calculated automatically to scale to the size of the
full model.
'gpu_split_auto' (bool): Automatically split model across available devices (default: True)
'gpu_split' (list[float]): Allocation for weights and (some) tensors, per device
'no_flash_attn' (bool): Turns off flash attention (increases vram usage)
"""
self.quiet = quiet
self.cache_fp8 = "cache_mode" in kwargs and kwargs["cache_mode"] == "FP8"
self.gpu_split = kwargs.get("gpu_split", None)
self.gpu_split_auto = kwargs.get("gpu_split_auto", True)
self.config = ExLlamaV2Config()
self.config.model_dir = str(model_directory.resolve())
self.config.prepare()
if "max_seq_len" in kwargs: self.config.max_seq_len = kwargs["max_seq_len"]
if "rope_scale" in kwargs: self.config.scale_pos_emb = kwargs["rope_scale"]
if "rope_alpha" in kwargs: self.config.scale_alpha_value = kwargs["rope_alpha"]
if "no_flash_attn" in kwargs: self.config.no_flash_attn = kwargs["no_flash_attn"]
if "low_mem" in kwargs and kwargs["low_mem"]:
self.config.set_low_mem()
chunk_size = min(kwargs.get("chunk_size", 2048), self.config.max_seq_len)
self.config.max_input_len = chunk_size
self.config.max_attn_size = chunk_size ** 2
self.draft_enabled = "draft_model_dir" in kwargs
if self.draft_enabled:
self.draft_config = ExLlamaV2Config()
self.draft_config.model_dir = kwargs["draft_model_dir"]
self.draft_config.prepare()
self.draft_config.max_seq_len = self.config.max_seq_len
if "draft_rope_alpha" in kwargs:
self.draft_config.scale_alpha_value = kwargs["draft_rope_alpha"]
else:
ratio = self.config.max_seq_len / self.draft_config.max_seq_len
alpha = -0.13436 + 0.80541 * ratio + 0.28833 * ratio ** 2
self.draft_config.scale_alpha_value = alpha
if "chunk_size" in kwargs:
self.draft_config.max_input_len = kwargs["chunk_size"]
self.draft_config.max_attn_size = kwargs["chunk_size"] ** 2
def get_model_path(self):
model_path = pathlib.Path(self.config.model_dir)
return model_path
def load(self, progress_callback = None):
"""
Load model
Args:
progress_callback (function, optional): A function to call for each module loaded. Prototype:
def progress(loaded_modules: int, total_modules: int)
"""
for _ in self.load_gen(progress_callback): pass
def load_gen(self, progress_callback = None):
"""
Load model, generator function
Args:
progress_callback (function, optional): A function to call for each module loaded. Prototype:
def progress(loaded_modules: int, total_modules: int)
"""
# Load tokenizer
self.tokenizer = ExLlamaV2Tokenizer(self.config)
# Load draft model
if self.draft_enabled:
self.draft_model = ExLlamaV2(self.draft_config)
if not self.quiet:
print("Loading draft model: " + self.draft_config.model_dir)
self.draft_cache = ExLlamaV2Cache(self.draft_model, lazy = True)
reserve = [auto_split_reserve_bytes] + [0] * 16
yield from self.draft_model.load_autosplit_gen(self.draft_cache, reserve_vram = reserve, last_id_only = True, callback_gen = progress_callback)
# Test VRAM allocation with a full-length forward pass
input_ids = torch.zeros((1, self.config.max_input_len), dtype = torch.long)
self.draft_model.forward(input_ids, cache = self.cache, preprocess_only = True)
# Load model
self.model = ExLlamaV2(self.config)
if not self.quiet:
print("Loading model: " + self.config.model_dir)
if not self.gpu_split_auto:
for value in self.model.load_gen(self.gpu_split, callback_gen = progress_callback):
if isinstance(value, str):
yield value
if self.cache_fp8:
self.cache = ExLlamaV2Cache_8bit(self.model, lazy = self.gpu_split_auto)
else:
self.cache = ExLlamaV2Cache(self.model, lazy = self.gpu_split_auto)
if self.gpu_split_auto:
reserve = [auto_split_reserve_bytes] + [0] * 16
yield from self.model.load_autosplit_gen(self.cache, reserve_vram = reserve, last_id_only = True, callback_gen = progress_callback)
# Test VRAM allocation with a full-length forward pass
input_ids = torch.zeros((1, self.config.max_input_len), dtype = torch.long)
self.model.forward(input_ids, cache = self.cache, preprocess_only = True)
# Create generator
self.generator = ExLlamaV2StreamingGenerator(self.model, self.cache, self.tokenizer, self.draft_model, self.draft_cache)
print("Model successfully loaded.")
def unload(self):
"""
Free all VRAM resources used by this model
"""
if self.model: self.model.unload()
self.model = None
if self.draft_model: self.draft_model.unload()
self.draft_model = None
self.config = None
self.cache = None
self.tokenizer = None
self.generator = None
gc.collect()
torch.cuda.empty_cache()
# Common function for token operations
def get_tokens(self, text: Optional[str], ids: Optional[List[int]], **kwargs):
if text:
# Assume token encoding
return self.tokenizer.encode(
text,
add_bos = kwargs.get("add_bos_token", True),
encode_special_tokens = kwargs.get("encode_special_tokens", True)
)
if ids:
# Assume token decoding
ids = torch.tensor([ids])
return self.tokenizer.decode(ids, decode_special_tokens = kwargs.get("decode_special_tokens", True))[0]
def generate(self, prompt: str, **kwargs):
gen = self.generate_gen(prompt, **kwargs)
reponse = "".join(gen)
return reponse
def generate_gen(self, prompt: str, **kwargs):
"""
Create generator function for prompt completion
Args:
prompt (str): Input prompt
**kwargs:
'token_healing' (bool): Use token healing (default: False)
'temperature' (float): Sampling temperature (default: 1.0)
'top_k' (int): Sampling top-K (default: 0)
'top_p' (float): Sampling top-P (default: 1.0)
'min_p' (float): Sampling min-P (default: 0.0)
'tfs' (float): Tail-free sampling (default: 0.0)
'typical' (float): Sampling typical (default: 0.0)
'mirostat' (bool): Use Mirostat (default: False)
'mirostat_tau' (float) Mirostat tau parameter (default: 1.5)
'mirostat_eta' (float) Mirostat eta parameter (default: 0.1)
'repetition_penalty' (float): Token repetition/presence penalty (default: 1.15)
'repetition_range' (int): Repetition penalty range (default: whole context)
'repetition_decay' (int): Repetition penalty range (default: same as range)
'stop' (list): List of stop strings/tokens to end response (default: [EOS])
'max_tokens' (int): Max no. tokens in response (default: 150)
'add_bos_token' (bool): Adds the BOS token to the start of the prompt (default: True)
'ban_eos_token' (bool): Bans the EOS token from generation (default: False)
'stream_interval' (float): Interval in seconds between each output chunk (default: immediate)
'generate_window' (int): Space to reserve at the end of the model's context when generating.
Rolls context window by the same amount if context length is exceeded to allow generating past
the models max_seq_len.
"""
token_healing = kwargs.get("token_healing", False)
max_tokens = kwargs.get("max_tokens", 150)
stream_interval = kwargs.get("stream_interval", 0)
generate_window = min(kwargs.get("generate_window", 512), max_tokens)
# Sampler settings
gen_settings = ExLlamaV2Sampler.Settings()
gen_settings.temperature = kwargs.get("temperature", 1.0)
gen_settings.top_k = kwargs.get("top_k", 1)
gen_settings.top_p = kwargs.get("top_p", 1.0)
gen_settings.min_p = kwargs.get("min_p", 0.0)
gen_settings.tfs = kwargs.get("tfs", 0.0)
gen_settings.typical = kwargs.get("typical", 0.0)
gen_settings.mirostat = kwargs.get("mirostat", False)
# Default tau and eta fallbacks don't matter if mirostat is off
gen_settings.mirostat_tau = kwargs.get("mirostat_tau", 1.5)
gen_settings.mirostat_eta = kwargs.get("mirostat_eta", 0.1)
gen_settings.token_repetition_penalty = kwargs.get("repetition_penalty", 1.0)
gen_settings.token_repetition_range = kwargs.get("repetition_range", self.config.max_seq_len)
gen_settings.token_repetition_decay = kwargs.get("repetition_decay", gen_settings.token_repetition_range)
# Ban the EOS token if specified
if kwargs.get("ban_eos_token", False):
gen_settings.disallow_tokens(self.tokenizer, [self.tokenizer.eos_token_id])
# Override sampler settings for temp = 0
if gen_settings.temperature == 0:
gen_settings.temperature = 1.0
gen_settings.top_k = 1
gen_settings.top_p = 0
gen_settings.typical = 0
# Stop conditions
self.generator.set_stop_conditions(kwargs.get("stop", [self.tokenizer.eos_token_id]))
# Tokenized context
ids = self.tokenizer.encode(
prompt,
add_bos=kwargs.get("add_bos_token", True),
encode_special_tokens = True
)
# Begin
generated_tokens = 0
full_response = ""
last_chunk_time = time.time()
save_tokens = torch.empty((1, 0), dtype = torch.bool)
chunk_buffer = ""
chunk_tokens = 0
while True:
# Ingest prompt
if chunk_tokens == 0:
ids = torch.cat((ids, save_tokens), dim = - 1)
save_tokens = torch.empty((1, 0), dtype = torch.bool)
overflow = ids.shape[-1] + generate_window - self.config.max_seq_len
active_ids = ids[:, max(0, overflow):]
chunk_tokens = self.config.max_seq_len - active_ids.shape[-1]
self.generator.begin_stream(active_ids, gen_settings, token_healing = token_healing)
# Generate
chunk, eos, tokens = self.generator.stream()
if token_healing:
ids[:, -1] = self.generator.sequence_ids[:, -2] # Extract healed token
token_healing = False
save_tokens = torch.cat((save_tokens, tokens), dim=-1)
chunk_buffer += chunk
generated_tokens += 1
chunk_tokens -= 1
# Yield output
now = time.time()
elapsed = now - last_chunk_time
if chunk_buffer != "" and (elapsed > stream_interval or eos or generated_tokens == max_tokens):
yield chunk_buffer
full_response += chunk_buffer
chunk_buffer = ""
last_chunk_time = now
if eos or generated_tokens == max_tokens: break