93 lines
3.2 KiB
Python
93 lines
3.2 KiB
Python
# SPDX-License-Identifier: Apache-2.0
|
|
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
|
|
"""CPU-only unit tests for the sleep-mode backend abstraction (RFC #34303).
|
|
|
|
These cover the registry/factory contract and capability flags. They do not
|
|
touch CUDA - the ``cumem`` suspend/resume path is exercised end-to-end on GPU
|
|
in ``tests/basic_correctness/test_cumem.py``.
|
|
"""
|
|
|
|
import pytest
|
|
|
|
from vllm.device_allocator.sleep_mode_backend import (
|
|
CuMemBackend,
|
|
SleepModeBackend,
|
|
SleepModeBackendFactory,
|
|
)
|
|
|
|
|
|
def test_cumem_is_the_default_registered_backend():
|
|
backend_cls = SleepModeBackendFactory.get_backend_class("cumem")
|
|
assert backend_cls is CuMemBackend
|
|
assert issubclass(backend_cls, SleepModeBackend)
|
|
|
|
|
|
def test_cumem_capability_flags():
|
|
# cumem leaves communicators untouched but does not preserve compiled
|
|
# artifacts, graphs, or durable state - these flags are what the executor and
|
|
# /health introspect to decide reinit / persistence behavior.
|
|
assert CuMemBackend.is_supported() is True
|
|
assert CuMemBackend.preserves_communicators() is True
|
|
assert CuMemBackend.preserves_compiled_artifacts() is False
|
|
assert CuMemBackend.preserves_graphs_with_communicators() is False
|
|
assert CuMemBackend.supports_durable_storage() is False
|
|
|
|
|
|
def test_new_backend_starts_in_running_state():
|
|
# Constructing a backend must not touch the GPU; only suspend/resume do.
|
|
assert CuMemBackend().state() == "RUNNING"
|
|
|
|
|
|
def test_unknown_backend_raises():
|
|
with pytest.raises(ValueError, match="Unsupported sleep-mode backend"):
|
|
SleepModeBackendFactory.get_backend_class("does-not-exist")
|
|
|
|
|
|
def test_duplicate_registration_raises():
|
|
with pytest.raises(ValueError, match="already registered"):
|
|
SleepModeBackendFactory.register_backend(
|
|
"cumem",
|
|
"vllm.device_allocator.sleep_mode_backend",
|
|
"CuMemBackend",
|
|
)
|
|
|
|
|
|
def test_third_party_backend_registration_and_resolution():
|
|
"""A plugin registers a backend by name; the factory resolves it lazily."""
|
|
name = "_pytest_dummy_backend"
|
|
try:
|
|
SleepModeBackendFactory.register_backend(
|
|
name,
|
|
"tests.v1.worker.test_sleep_mode_backend",
|
|
"DummyBackend",
|
|
)
|
|
resolved = SleepModeBackendFactory.get_backend_class(name)
|
|
assert resolved is DummyBackend
|
|
assert resolved.supports_durable_storage() is True
|
|
finally:
|
|
SleepModeBackendFactory._registry.pop(name, None)
|
|
|
|
|
|
def test_suspend_resume_state_transitions():
|
|
"""Lifecycle state advances RUNNING -> SUSPENDED -> RUNNING without GPU."""
|
|
backend = DummyBackend()
|
|
assert backend.state() == "RUNNING"
|
|
backend.suspend(level=1)
|
|
assert backend.state() == "SUSPENDED"
|
|
backend.resume()
|
|
assert backend.state() == "RUNNING"
|
|
|
|
|
|
class DummyBackend(SleepModeBackend):
|
|
"""A no-GPU backend used to exercise lifecycle + registration in CPU tests."""
|
|
|
|
def suspend(self, level: int = 1) -> None:
|
|
self._state = "SUSPENDED"
|
|
|
|
def resume(self, tags: list[str] | None = None) -> None:
|
|
self._state = "RUNNING"
|
|
|
|
@classmethod
|
|
def supports_durable_storage(cls) -> bool:
|
|
return True
|