ColossalAI/tests/test_engine/test_gradient_accumluation.py

100 lines
3.3 KiB
Python

import os
from functools import partial
from pathlib import Path
import colossalai
from colossalai.testing.utils import rerun_if_address_is_in_use
import pytest
import torch
import torch.multiprocessing as mp
import torch.nn as nn
from colossalai.core import global_context as gpc
from colossalai.logging import get_dist_logger
from colossalai.utils import free_port, get_dataloader
from colossalai.testing import rerun_if_address_is_in_use
from torch.optim import Adam
from torchvision import transforms
from torchvision.datasets import CIFAR10
from torchvision.models import resnet18
# Config
BATCH_SIZE = 2
NUM_CLASSES = 10
CONFIG = dict(parallel=dict(pipeline=dict(size=1), tensor=dict(size=1, mode=None)),
clip_grad_norm=1.0,
gradient_accumulation=4)
def run_no_pipeline(rank, world_size, port):
# init dist env
colossalai.launch(config=CONFIG, rank=rank, world_size=world_size, host='localhost', port=port, backend='nccl')
# build model
model = resnet18(num_classes=10)
# build dataloaders
train_dataset = CIFAR10(root=Path(os.environ['DATA']),
download=True,
transform=transforms.Compose([
transforms.ToTensor(),
transforms.Normalize(mean=(0.5, 0.5, 0.5), std=(0.5, 0.5, 0.5))
]))
train_dataloader = get_dataloader(dataset=train_dataset,
shuffle=True,
batch_size=BATCH_SIZE,
pin_memory=True,
drop_last=True)
# build optimizer
optimizer = Adam(model.parameters(), lr=0.001)
criterion = nn.CrossEntropyLoss()
engine, train_dataloader, *args = colossalai.initialize(model=model,
optimizer=optimizer,
criterion=criterion,
train_dataloader=train_dataloader)
logger = get_dist_logger()
rank = torch.distributed.get_rank()
param_track = []
grad_track = []
next(model.parameters()).retain_grad()
engine.train()
step = 0
for img, label in train_dataloader:
engine.zero_grad()
img = img.cuda()
label = label.cuda()
output = engine(img)
loss = engine.criterion(output, label)
engine.backward(loss)
engine.step()
# check
param_track.append(next(model.parameters())[0].clone())
grad_track.append(next(model.parameters()).grad[0].clone())
step += 1
if step == CONFIG['gradient_accumulation']:
break
assert not torch.all(grad_track[0] == grad_track[-1]), 'grad should be different in different iterations'
assert torch.all(param_track[0] == param_track[1]) and not torch.all(param_track[0] == param_track[-1]), \
'param should be the same in the first few iterations and only changed in the last iteration'
gpc.destroy()
torch.cuda.empty_cache()
@pytest.mark.dist
@rerun_if_address_is_in_use()
def test_engine():
world_size = 4
func = partial(run_no_pipeline, world_size=world_size, port=free_port())
mp.spawn(func, nprocs=world_size)
if __name__ == '__main__':
test_engine()