llama-stack/llama_stack/providers/inline/inference/meta_reference/model_parallel.py
Ashwin Bharambe b8f1561956
feat: introduce llama4 support (#1877)
As title says. Details in README, elsewhere.
2025-04-05 11:53:35 -07:00

97 lines
3 KiB
Python

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the terms described in the LICENSE file in
# the root directory of this source tree.
from copy import deepcopy
from functools import partial
from typing import Any, Callable, Generator
from llama_stack.models.llama.llama3.chat_format import ChatFormat as Llama3ChatFormat
from llama_stack.models.llama.llama4.chat_format import ChatFormat as Llama4ChatFormat
from llama_stack.providers.utils.inference.prompt_adapter import (
ChatCompletionRequestWithRawContent,
CompletionRequestWithRawContent,
)
from .parallel_utils import ModelParallelProcessGroup
class ModelRunner:
def __init__(self, llama):
self.llama = llama
# the `task` object is the same that is sent to `ModelParallelProcessGroup.run_inference()`
def __call__(self, req: Any):
if isinstance(req, ChatCompletionRequestWithRawContent):
return self.llama.chat_completion(req)
elif isinstance(req, CompletionRequestWithRawContent):
return self.llama.completion(req)
else:
raise ValueError(f"Unexpected task type {type(req)}")
def init_model_cb(
builder_fn: Callable,
params: list[Any],
):
llama = builder_fn(*params)
return ModelRunner(llama)
class LlamaModelParallelGenerator:
"""
This abstraction exists so
- we can run model parallel code without needing to run the CLIs via torchrun
- this also enables use model parallel code within a notebook context.
A Context Manager is used to ensure that the model parallel process is started and stopped
correctly. This does make the ergonomics a little awkward, because it isn't immediately
clear at the callsite why we need to use a context manager.
"""
def __init__(
self,
model_parallel_size: int,
builder_fn: Callable,
builder_params: list[Any],
formatter: Llama3ChatFormat | Llama4ChatFormat,
):
self.model_parallel_size = model_parallel_size
self.builder_fn = builder_fn
self.builder_params = builder_params
self.formatter = formatter
def start(self):
self.__enter__()
def stop(self):
self.__exit__(None, None, None)
def __enter__(self):
self.group = ModelParallelProcessGroup(
self.model_parallel_size,
init_model_cb=partial(init_model_cb, self.builder_fn, self.builder_params),
)
self.group.start()
return self
def __exit__(self, exc_type, exc_value, exc_traceback):
self.group.stop()
def completion(
self,
request: CompletionRequestWithRawContent,
) -> Generator:
req_obj = deepcopy(request)
gen = self.group.run_inference(req_obj)
yield from gen
def chat_completion(
self,
request: ChatCompletionRequestWithRawContent,
) -> Generator:
req_obj = deepcopy(request)
gen = self.group.run_inference(req_obj)
yield from gen