ColossalAI/tests/test_amp/test_naive_fp16.py

96 lines
3.4 KiB
Python

import torch
import colossalai
import torch.multiprocessing as mp
from colossalai.amp import convert_to_naive_amp, convert_to_apex_amp
from tests.components_to_test.registry import non_distributed_component_funcs
from colossalai.testing import assert_close_loose, rerun_on_exception
from colossalai.utils import free_port
from colossalai.amp import convert_to_naive_amp, convert_to_apex_amp
from tests.components_to_test.registry import non_distributed_component_funcs
import copy
import pytest
from functools import partial
def check_equal(a, b):
"""
This function checks if two tensors are equal within tolerance
"""
assert torch.allclose(a.float(), b.float(), rtol=1e-4, atol=1e-3), f'a = {a}, b = {b}'
def run_naive_amp():
"""
In this test, we compare the naive fp16 optimizer implemented in colossalai
and fp32 torch optimizer
"""
torch.backends.cudnn.benchmark = False
torch.backends.cudnn.deterministic = True
# create layer
test_models = ['repeated_computed_layers', 'nested_model', 'resnet18']
for test_name in test_models:
get_component_func = non_distributed_component_funcs.get_callable(test_name)
model_builder, train_dataloader, _, optim_class, _ = get_component_func()
# create model
naive_amp_model = model_builder(checkpoint=True).cuda()
apex_amp_model = copy.deepcopy(naive_amp_model)
# create optimizer
naive_amp_optimizer = optim_class(naive_amp_model.parameters(), lr=1e-3)
apex_amp_optimizer = optim_class(apex_amp_model.parameters(), lr=1e-3)
# inject naive and apex amp
naive_amp_config = dict(initial_scale=128)
naive_amp_model, naive_amp_optimizer = convert_to_naive_amp(naive_amp_model, naive_amp_optimizer,
naive_amp_config)
apex_amp_config = dict(opt_level='O2', loss_scale=128, keep_batchnorm_fp32=False)
apex_amp_model, apex_amp_optimizer = convert_to_apex_amp(apex_amp_model, apex_amp_optimizer, apex_amp_config)
# create data
data_iter = iter(train_dataloader)
data, label = next(data_iter)
data = data.cuda()
# forward pass
naive_amp_output = naive_amp_model(data)
apex_amp_output = apex_amp_model(data)
assert_close_loose(naive_amp_output, apex_amp_output)
# backward
naive_amp_optimizer.backward(naive_amp_output.mean())
apex_amp_optimizer.backward(apex_amp_output.mean())
# check grad
for naive_amp_param, apex_amp_param in zip(naive_amp_model.parameters(), apex_amp_model.parameters()):
assert_close_loose(naive_amp_param.grad, apex_amp_param.grad)
# step
naive_amp_optimizer.step()
apex_amp_optimizer.step()
# check updated param
for naive_amp_param, apex_amp_param in zip(naive_amp_model.parameters(), apex_amp_model.parameters()):
assert_close_loose(naive_amp_param, apex_amp_param)
def run_dist(rank, world_size, port):
colossalai.launch(config=dict(), rank=rank, world_size=world_size, port=port, host='localhost')
run_naive_amp()
@pytest.mark.dist
@rerun_on_exception(exception_type=mp.ProcessRaisedException, pattern=".*Address already in use.*")
def test_naive_amp():
world_size = 1
run_func = partial(run_dist, world_size=world_size, port=free_port())
mp.spawn(run_func, nprocs=world_size)
if __name__ == '__main__':
test_naive_amp()