ColossalAI/tests/test_data/test_data_parallel_sampler.py

63 lines
1.8 KiB
Python

#!/usr/bin/env python
# -*- encoding: utf-8 -*-
import os
from pathlib import Path
import pytest
import torch
import torch.distributed as dist
from torchvision import datasets, transforms
import colossalai
from colossalai.context import Config, ParallelMode
from colossalai.core import global_context as gpc
from colossalai.testing import rerun_if_address_is_in_use, spawn
from colossalai.utils import get_dataloader
CONFIG = Config(dict(
parallel=dict(
pipeline=dict(size=1),
tensor=dict(size=1, mode=None),
),
seed=1024,
))
def run_data_sampler(rank, world_size, port):
dist_args = dict(config=CONFIG, rank=rank, world_size=world_size, backend='gloo', port=port, host='localhost')
colossalai.launch(**dist_args)
print('finished initialization')
# build dataset
transform_pipeline = [transforms.ToTensor()]
transform_pipeline = transforms.Compose(transform_pipeline)
dataset = datasets.CIFAR10(root=Path(os.environ['DATA']), train=True, download=True, transform=transform_pipeline)
# build dataloader
dataloader = get_dataloader(dataset, batch_size=8, add_sampler=True)
data_iter = iter(dataloader)
img, label = data_iter.next()
img = img[0]
if gpc.get_local_rank(ParallelMode.DATA) != 0:
img_to_compare = img.clone()
else:
img_to_compare = img
dist.broadcast(img_to_compare, src=0, group=gpc.get_group(ParallelMode.DATA))
if gpc.get_local_rank(ParallelMode.DATA) != 0:
assert not torch.equal(
img, img_to_compare), 'Same image was distributed across ranks but expected it to be different'
torch.cuda.empty_cache()
@rerun_if_address_is_in_use()
def test_data_sampler():
spawn(run_data_sampler, 4)
if __name__ == '__main__':
test_data_sampler()