Files
vllm-omni/tests/diffusion/distributed/test_comm.py
T

518 lines
15 KiB
Python

# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM-Omni project
"""Tests for SeqAllToAll4D, SeqAllToAll5D, and RingComm communication primitives.
CPU tests use gloo on CPU tensors (no GPU). Nightly parity tests run the same
checks on real multi-GPU NCCL collectives.
"""
from __future__ import annotations
import os
from typing import Literal
import pytest
import torch
from tests.helpers.distributed import configure_cpu_collective_worker, start_collective_workers
from tests.helpers.mark import hardware_marks
from vllm_omni.diffusion.distributed.comm import RingComm, SeqAllToAll4D, SeqAllToAll5D
from vllm_omni.diffusion.distributed.parallel_state import (
destroy_distributed_env,
get_sp_group,
init_distributed_environment,
initialize_model_parallel,
)
from vllm_omni.platforms import current_omni_platform
_L4_TWO_GPU = hardware_marks(res={"cuda": ["L4", "B200"]}, num_cards=2)
_L4_FOUR_GPU = hardware_marks(res={"cuda": ["L4", "B200"]}, num_cards=4)
DeviceKind = Literal["cpu", "cuda"]
def _update_environment_variables(envs_dict: dict[str, str]) -> None:
for key, value in envs_dict.items():
os.environ[key] = value
def _worker_device(local_rank: int, device_kind: DeviceKind) -> torch.device:
if device_kind == "cpu":
return torch.device("cpu")
return torch.device(f"{current_omni_platform.device_type}:{local_rank}")
def _init_worker(
local_rank: int,
world_size: int,
master_port: int,
device_kind: DeviceKind,
) -> None:
_update_environment_variables(
{
"RANK": str(local_rank),
"LOCAL_RANK": str(local_rank),
"WORLD_SIZE": str(world_size),
"MASTER_ADDR": "localhost",
"MASTER_PORT": str(master_port),
}
)
if device_kind == "cpu":
configure_cpu_collective_worker()
backend = "gloo" if device_kind == "cpu" else None
init_distributed_environment(backend=backend)
def _close_tolerance(dtype: torch.dtype) -> tuple[float, float]:
if dtype == torch.bfloat16:
return 1e-3, 1e-3
if dtype == torch.float16:
return 1e-3, 1e-3
return 1e-5, 1e-5
def _run_4d_identity(
local_rank: int,
world_size: int,
dtype: torch.dtype,
batch_size: int,
seq_len_per_rank: int,
num_heads: int,
head_size: int,
use_sync: bool,
device_kind: DeviceKind,
master_port: int,
) -> None:
device = _worker_device(local_rank, device_kind)
if device_kind == "cuda":
current_omni_platform.set_device(device)
_init_worker(local_rank, world_size, master_port, device_kind)
initialize_model_parallel(ulysses_degree=world_size)
sp_group = get_sp_group().ulysses_group
torch.manual_seed(42 + local_rank)
input_tensor = torch.randn(
batch_size,
seq_len_per_rank,
num_heads,
head_size,
dtype=dtype,
device=device,
)
original_input = input_tensor.clone()
intermediate = SeqAllToAll4D.apply(sp_group, input_tensor, 2, 1, use_sync)
expected_intermediate_shape = (
batch_size,
seq_len_per_rank * world_size,
num_heads // world_size,
head_size,
)
assert intermediate.shape == expected_intermediate_shape, (
f"Intermediate shape mismatch: expected {expected_intermediate_shape}, got {intermediate.shape}"
)
output = SeqAllToAll4D.apply(sp_group, intermediate, 1, 2, use_sync)
assert output.shape == original_input.shape, (
f"Output shape mismatch: expected {original_input.shape}, got {output.shape}"
)
rtol, atol = _close_tolerance(dtype)
torch.testing.assert_close(
output,
original_input,
rtol=rtol,
atol=atol,
msg="Output does not match original input after two all-to-all operations",
)
destroy_distributed_env()
def _run_5d_identity(
local_rank: int,
world_size: int,
dtype: torch.dtype,
batch_size: int,
seq_len_per_rank: int,
num_heads: int,
head_size: int,
use_sync: bool,
device_kind: DeviceKind,
master_port: int,
) -> None:
device = _worker_device(local_rank, device_kind)
if device_kind == "cuda":
current_omni_platform.set_device(device)
_init_worker(local_rank, world_size, master_port, device_kind)
initialize_model_parallel(ulysses_degree=world_size)
sp_group = get_sp_group().ulysses_group
torch.manual_seed(42 + local_rank)
input_tensor = torch.randn(
batch_size,
seq_len_per_rank,
3,
num_heads,
head_size,
dtype=dtype,
device=device,
)
original_input = input_tensor.clone()
intermediate = SeqAllToAll5D.apply(sp_group, input_tensor, 3, 1, use_sync)
expected_intermediate_shape = (
batch_size,
seq_len_per_rank * world_size,
3,
num_heads // world_size,
head_size,
)
assert intermediate.shape == expected_intermediate_shape, (
f"Intermediate shape mismatch: expected {expected_intermediate_shape}, got {intermediate.shape}"
)
output = SeqAllToAll5D.apply(sp_group, intermediate, 1, 3, use_sync)
assert output.shape == original_input.shape, (
f"Output shape mismatch: expected {original_input.shape}, got {output.shape}"
)
rtol, atol = _close_tolerance(dtype)
torch.testing.assert_close(
output,
original_input,
rtol=rtol,
atol=atol,
msg="Output does not match original input after two all-to-all operations",
)
destroy_distributed_env()
def _run_ring_p2p(
local_rank: int,
world_size: int,
dtype: torch.dtype,
batch_size: int,
num_heads: int,
head_size: int,
device_kind: DeviceKind,
master_port: int,
) -> None:
device = _worker_device(local_rank, device_kind)
if device_kind == "cuda":
current_omni_platform.set_device(device)
try:
_init_worker(local_rank, world_size, master_port, device_kind)
initialize_model_parallel(ring_degree=world_size)
sp_group = get_sp_group()
comm = RingComm(sp_group.ring_group)
input_tensor = torch.full(
(batch_size, num_heads, head_size),
fill_value=float(local_rank + 1),
dtype=dtype,
device=device,
)
recv_tensor = comm.send_recv(input_tensor)
comm.commit()
comm.wait()
prev_rank = (local_rank - 1 + world_size) % world_size
expected_value = float(prev_rank + 1)
expected_tensor = torch.full_like(recv_tensor, fill_value=expected_value)
rtol, atol = _close_tolerance(dtype)
torch.testing.assert_close(
recv_tensor,
expected_tensor,
rtol=rtol,
atol=atol,
msg=f"[Rank {local_rank}] Ring P2P data mismatch",
)
if device_kind == "cpu":
# P2P completion only synchronizes neighbors. Keep fast CPU ranks
# alive until every rank has finished constructing and using groups.
torch.distributed.barrier()
finally:
destroy_distributed_env()
def _spawn_4d_identity(
*,
world_size: int,
dtype: torch.dtype,
batch_size: int,
seq_len_per_rank: int,
num_heads: int,
head_size: int,
use_sync: bool,
device_kind: DeviceKind,
master_port: int,
) -> None:
start_collective_workers(
_run_4d_identity,
args=(
world_size,
dtype,
batch_size,
seq_len_per_rank,
num_heads,
head_size,
use_sync,
device_kind,
master_port,
),
nprocs=world_size,
device_kind=device_kind,
)
def _spawn_5d_identity(
*,
world_size: int,
dtype: torch.dtype,
batch_size: int,
seq_len_per_rank: int,
num_heads: int,
head_size: int,
use_sync: bool,
device_kind: DeviceKind,
master_port: int,
) -> None:
start_collective_workers(
_run_5d_identity,
args=(
world_size,
dtype,
batch_size,
seq_len_per_rank,
num_heads,
head_size,
use_sync,
device_kind,
master_port,
),
nprocs=world_size,
device_kind=device_kind,
)
def _spawn_ring_p2p(
*,
world_size: int,
dtype: torch.dtype,
batch_size: int,
num_heads: int,
head_size: int,
device_kind: DeviceKind,
master_port: int,
) -> None:
start_collective_workers(
_run_ring_p2p,
args=(world_size, dtype, batch_size, num_heads, head_size, device_kind, master_port),
nprocs=world_size,
device_kind=device_kind,
)
def _require_heads_divisible(num_heads: int, world_size: int) -> None:
if num_heads % world_size != 0:
pytest.skip(f"num_heads ({num_heads}) not divisible by world_size ({world_size})")
def _require_gpus(world_size: int) -> None:
available_gpus = current_omni_platform.get_device_count()
if available_gpus < world_size:
pytest.skip(f"Test requires {world_size} GPUs but only {available_gpus} available")
# ---------------------------------------------------------------------------
# CPU: gloo collectives on CPU tensors (no GPU)
# ---------------------------------------------------------------------------
@pytest.mark.core_model
@pytest.mark.diffusion
@pytest.mark.cpu
@pytest.mark.parametrize("world_size", [2, 4])
@pytest.mark.parametrize("use_sync", [False, True])
def test_4d_identity(world_size: int, use_sync: bool):
_require_heads_divisible(8, world_size)
_spawn_4d_identity(
world_size=world_size,
dtype=torch.float32,
batch_size=2,
seq_len_per_rank=8,
num_heads=8,
head_size=32,
use_sync=use_sync,
device_kind="cpu",
master_port=29610,
)
@pytest.mark.core_model
@pytest.mark.diffusion
@pytest.mark.cpu
@pytest.mark.parametrize("world_size", [2, 4])
@pytest.mark.parametrize("use_sync", [False, True])
def test_5d_identity(world_size: int, use_sync: bool):
_require_heads_divisible(8, world_size)
_spawn_5d_identity(
world_size=world_size,
dtype=torch.float32,
batch_size=2,
seq_len_per_rank=8,
num_heads=8,
head_size=32,
use_sync=use_sync,
device_kind="cpu",
master_port=29611,
)
@pytest.mark.core_model
@pytest.mark.diffusion
@pytest.mark.cpu
@pytest.mark.parametrize("world_size", [2, 4])
def test_ring_p2p(world_size: int):
_spawn_ring_p2p(
world_size=world_size,
dtype=torch.float32,
batch_size=2,
num_heads=8,
head_size=128,
device_kind="cpu",
master_port=29612,
)
# ---------------------------------------------------------------------------
# Nightly: same checks on real multi-GPU NCCL collectives
# ---------------------------------------------------------------------------
@pytest.mark.full_model
@pytest.mark.diffusion
@pytest.mark.parallel
@pytest.mark.parametrize(
"world_size",
[
pytest.param(2, marks=_L4_TWO_GPU),
pytest.param(4, marks=_L4_FOUR_GPU),
],
)
@pytest.mark.parametrize("dtype", [torch.float16, torch.bfloat16])
@pytest.mark.parametrize("use_sync", [False, True])
def test_4d_identity_parity(world_size: int, dtype: torch.dtype, use_sync: bool):
_require_gpus(world_size)
_require_heads_divisible(8, world_size)
_spawn_4d_identity(
world_size=world_size,
dtype=dtype,
batch_size=2,
seq_len_per_rank=8,
num_heads=8,
head_size=32,
use_sync=use_sync,
device_kind="cuda",
master_port=29500,
)
@pytest.mark.full_model
@pytest.mark.diffusion
@pytest.mark.parallel
@pytest.mark.parametrize(
"world_size",
[
pytest.param(2, marks=_L4_TWO_GPU),
pytest.param(4, marks=_L4_FOUR_GPU),
],
)
@pytest.mark.parametrize("dtype", [torch.float16, torch.bfloat16])
@pytest.mark.parametrize("use_sync", [False, True])
def test_5d_identity_parity(world_size: int, dtype: torch.dtype, use_sync: bool):
_require_gpus(world_size)
_require_heads_divisible(8, world_size)
_spawn_5d_identity(
world_size=world_size,
dtype=dtype,
batch_size=2,
seq_len_per_rank=8,
num_heads=8,
head_size=32,
use_sync=use_sync,
device_kind="cuda",
master_port=29502,
)
@pytest.mark.full_model
@pytest.mark.diffusion
@pytest.mark.parallel
@pytest.mark.parametrize(
"world_size",
[
pytest.param(2, marks=_L4_TWO_GPU),
pytest.param(4, marks=_L4_FOUR_GPU),
],
)
@pytest.mark.parametrize("dtype", [torch.float16, torch.bfloat16])
def test_ring_p2p_parity(world_size: int, dtype: torch.dtype):
_require_gpus(world_size)
_spawn_ring_p2p(
world_size=world_size,
dtype=dtype,
batch_size=2,
num_heads=8,
head_size=128,
device_kind="cuda",
master_port=29501,
)
def _run_fused_qkv_matches_three_4d(
local_rank: int,
world_size: int,
device_kind: DeviceKind,
master_port: int,
) -> None:
"""LingBot's fused (B, S/N, 3, H, D) exchange must equal three per-tensor 4D exchanges."""
from vllm_omni.diffusion.distributed.comm import all_to_all_5D
device = _worker_device(local_rank, device_kind)
if device_kind == "cuda":
current_omni_platform.set_device(device)
_init_worker(local_rank, world_size, master_port, device_kind)
initialize_model_parallel(ulysses_degree=world_size)
sp_group = get_sp_group().ulysses_group
try:
batch, seq_per_rank, heads, head_size = 1, 6, 4 * world_size, 8
# Distinguishable values: rank, q/k/v index, position, head, feature.
base = torch.arange(seq_per_rank * heads * head_size, dtype=torch.float32, device=device).reshape(
batch, seq_per_rank, heads, head_size
)
tensors = [base + 1000.0 * local_rank + 100000.0 * which for which in range(3)]
separate = [SeqAllToAll4D.apply(sp_group, t, 2, 1, False) for t in tensors]
fused = all_to_all_5D(torch.stack(tensors, dim=2), scatter_idx=3, gather_idx=1, group=sp_group)
assert fused.shape == (batch, seq_per_rank * world_size, 3, heads // world_size, head_size)
for which, expected in enumerate(separate):
assert torch.equal(fused.unbind(2)[which], expected), f"q/k/v index {which} differs on rank {local_rank}"
finally:
destroy_distributed_env()
@pytest.mark.core_model
@pytest.mark.diffusion
@pytest.mark.cpu
@pytest.mark.parametrize("world_size", [2, 4])
def test_fused_qkv_all_to_all_matches_three_4d_exchanges_cpu(world_size: int) -> None:
start_collective_workers(
_run_fused_qkv_matches_three_4d,
args=(world_size, "cpu", 29613),
nprocs=world_size,
device_kind="cpu",
)