| 1 | # SPDX-License-Identifier: Apache-2.0 |
| 2 | # SPDX-FileCopyrightText: Copyright contributors to the vLLM project |
| 3 | |
| 4 | import queue |
| 5 | import random |
| 6 | import typing |
| 7 | |
| 8 | import pytest |
| 9 | import torch |
| 10 | import torch.distributed as dist |
| 11 | import torch.multiprocessing as mp |
| 12 | |
| 13 | import vllm.envs as envs |
| 14 | from vllm.config import ParallelConfig, VllmConfig, set_current_vllm_config |
| 15 | from vllm.distributed import cleanup_dist_env_and_memory |
| 16 | from vllm.distributed.communication_op import tensor_model_parallel_all_reduce |
| 17 | from vllm.distributed.device_communicators.cuda_communicator import CudaCommunicator |
| 18 | from vllm.distributed.parallel_state import ( |
| 19 | get_tp_group, |
| 20 | init_distributed_environment, |
| 21 | initialize_model_parallel, |
| 22 | ) |
| 23 | from vllm.engine.arg_utils import EngineArgs |
| 24 | from vllm.engine.llm_engine import LLMEngine |
| 25 | from vllm.platforms import current_platform |
| 26 | from vllm.utils.system_utils import update_environment_variables |
| 27 | |
| 28 | torch.manual_seed(42) |
| 29 | random.seed(44) |
| 30 | |
| 31 | test_size_elements = 1024 * 1024 |
| 32 | |
| 33 | |
| 34 | def symm_mem_allreduce_worker(local_rank: int, world_size: int, q: mp.Queue): |
| 35 | monkeypatch = pytest.MonkeyPatch() |
| 36 | config = VllmConfig(parallel_config=ParallelConfig(tensor_parallel_size=world_size)) |
| 37 | |
| 38 | with monkeypatch.context() as m, set_current_vllm_config(config): |
| 39 | m.delenv("CUDA_VISIBLE_DEVICES", raising=False) |
| 40 | dtype = torch.bfloat16 |
| 41 | device = torch.device(f"cuda:{local_rank}") |
| 42 | torch.accelerator.set_device_index(device) |
| 43 | torch.set_default_device(device) |
| 44 | torch.set_default_dtype(dtype) |
| 45 | update_environment_variables( |
| 46 | { |
| 47 | "RANK": str(local_rank), |
| 48 | "LOCAL_RANK": str(local_rank), |
| 49 | "WORLD_SIZE": str(world_size), |
| 50 | "MASTER_ADDR": "localhost", |
| 51 | "MASTER_PORT": "12345", |
| 52 | } |
| 53 | ) |
| 54 | |
| 55 | init_distributed_environment() |
| 56 | initialize_model_parallel(tensor_model_parallel_size=world_size) |
| 57 | |
| 58 | cuda_communicator = typing.cast( |
| 59 | CudaCommunicator, get_tp_group().device_communicator |
| 60 | ) |
| 61 | symm_mem_comm = cuda_communicator.symm_mem_comm |
| 62 | if symm_mem_comm is None or symm_mem_comm.disabled: |
| 63 | # can't use skip under multiprocessing |
| 64 | q.put("SymmMemCommunicator is not available or disabled.") |
| 65 | return |
| 66 | |
| 67 | inp_direct_symm_mem = torch.randint( |
| 68 | 1, 23, (test_size_elements,), dtype=dtype, device=device |
| 69 | ) |
| 70 | if not symm_mem_comm.should_use_symm_mem(inp_direct_symm_mem): |
| 71 | # can't use skip under multiprocessing |
| 72 | q.put("SymmMemCommunicator isn't used for this world and input size.") |
| 73 | return |
| 74 | |
| 75 | original_inp_direct_symm_mem = inp_direct_symm_mem.clone() |
| 76 | out_direct_symm_mem = symm_mem_comm.all_reduce(inp_direct_symm_mem) |
| 77 | assert out_direct_symm_mem is not None |
| 78 | |
| 79 | group = get_tp_group().device_group |
| 80 | dist.all_reduce(original_inp_direct_symm_mem, group=group) |
| 81 | torch.testing.assert_close( |
| 82 | out_direct_symm_mem, original_inp_direct_symm_mem, atol=2.5, rtol=0.1 |
| 83 | ) |
| 84 | |
| 85 | # Test tensor_model_parallel_all_reduce which should use symm_mem |
| 86 | inp_tensor_parallel = torch.randint( |
| 87 | -23, 1, (test_size_elements,), dtype=dtype, device=device |
| 88 | ) |
| 89 | original_inp_tensor_parallel = inp_tensor_parallel.clone() |
| 90 | out_tensor_parallel = tensor_model_parallel_all_reduce(inp_tensor_parallel) |
| 91 | dist.all_reduce(original_inp_tensor_parallel, group=group) |
| 92 | torch.testing.assert_close( |
| 93 | out_tensor_parallel, original_inp_tensor_parallel, atol=2.5, rtol=0.1 |
| 94 | ) |
| 95 | |
| 96 | |
| 97 | @pytest.mark.skipif( |
| 98 | not current_platform.is_cuda(), |
| 99 | reason="SymmMemAllreduce is only available for CUDA platforms.", |
| 100 | ) |
| 101 | @pytest.mark.parametrize("tp_size", [2]) |
| 102 | @pytest.mark.parametrize("pipeline_parallel_size", [1]) |
| 103 | @pytest.mark.skipif(envs.VLLM_TARGET_DEVICE not in ["cuda"], reason="Only test on CUDA") |
| 104 | def test_symm_mem_allreduce( |
| 105 | monkeypatch: pytest.MonkeyPatch, tp_size, pipeline_parallel_size |
| 106 | ): |
| 107 | world_size = tp_size * pipeline_parallel_size |
| 108 | if world_size > torch.accelerator.device_count(): |
| 109 | pytest.skip("Not enough GPUs to run the test.") |
| 110 | q = mp.get_context("spawn").Queue() |
| 111 | mp.spawn(symm_mem_allreduce_worker, args=(world_size, q), nprocs=world_size) |
| 112 | try: |
| 113 | val = q.get(timeout=1) |
| 114 | except queue.Empty: |
| 115 | val = None |
| 116 | finally: |
| 117 | cleanup_dist_env_and_memory() |
| 118 | if val is not None: |
| 119 | pytest.skip(val) |
| 120 | |
| 121 | |
| 122 | @pytest.mark.skipif( |
| 123 | not current_platform.is_cuda(), |
| 124 | reason="SymmMemAllreduce is only available for CUDA platforms.", |
| 125 | ) |
| 126 | @pytest.mark.skipif(envs.VLLM_TARGET_DEVICE not in ["cuda"], reason="Only test on CUDA") |
| 127 | def test_dp_with_symm_mem_allreduce(monkeypatch: pytest.MonkeyPatch): |
| 128 | world_size = 4 |
| 129 | if world_size > torch.accelerator.device_count(): |
| 130 | pytest.skip("Not enough GPUs to run the test.") |
| 131 | # Verify that the DataParallel runs without error |
| 132 | engine_args = EngineArgs( |
| 133 | model="distilbert/distilgpt2", |
| 134 | enforce_eager=True, |
| 135 | enable_prefix_caching=True, |
| 136 | data_parallel_size=2, |
| 137 | tensor_parallel_size=2, |
| 138 | data_parallel_backend="mp", |
| 139 | ) |
| 140 | LLMEngine.from_engine_args(engine_args) |