lightning/benchmarks/test_rnn_parity.py

154 lines
4.2 KiB
Python

import time
import numpy as np
import pytest
import torch
import torch.nn as nn
import torch.nn.functional as F
from torch.utils.data import Dataset, DataLoader
import tests.base.utils as tutils
from pytorch_lightning import Trainer, LightningModule, seed_everything
class AverageDataset(Dataset):
def __init__(self, dataset_len=300, sequence_len=100):
self.dataset_len = dataset_len
self.sequence_len = sequence_len
self.input_seq = torch.randn(dataset_len, sequence_len, 10)
top, bottom = self.input_seq.chunk(2, -1)
self.output_seq = top + bottom.roll(shifts=1, dims=-1)
def __len__(self):
return self.dataset_len
def __getitem__(self, item):
return self.input_seq[item], self.output_seq[item]
class ParityRNN(LightningModule):
def __init__(self):
super(ParityRNN, self).__init__()
self.rnn = nn.LSTM(10, 20, batch_first=True)
self.linear_out = nn.Linear(in_features=20, out_features=5)
def forward(self, x):
seq, last = self.rnn(x)
return self.linear_out(seq)
def training_step(self, batch, batch_nb):
x, y = batch
y_hat = self(x)
loss = F.mse_loss(y_hat, y)
return {'loss': loss}
def configure_optimizers(self):
return torch.optim.Adam(self.parameters(), lr=0.02)
def train_dataloader(self):
return DataLoader(AverageDataset(), batch_size=30)
@pytest.mark.skipif(not torch.cuda.is_available(), reason="test requires GPU machine")
def test_pytorch_parity(tmpdir):
"""
Verify that the same pytorch and lightning models achieve the same results
:param tmpdir:
:return:
"""
num_epochs = 2
num_rums = 3
lightning_outs, pl_times = lightning_loop(ParityRNN, num_rums, num_epochs)
manual_outs, pt_times = vanilla_loop(ParityRNN, num_rums, num_epochs)
# make sure the losses match exactly to 5 decimal places
for pl_out, pt_out in zip(lightning_outs, manual_outs):
np.testing.assert_almost_equal(pl_out, pt_out, 8)
tutils.assert_speed_parity(pl_times, pt_times, num_epochs)
def vanilla_loop(MODEL, num_runs=10, num_epochs=10):
"""
Returns an array with the last loss from each epoch for each run
"""
device = torch.device('cuda' if torch.cuda.is_available() else "cpu")
errors = []
times = []
torch.backends.cudnn.deterministic = True
for i in range(num_runs):
time_start = time.perf_counter()
# set seed
seed = i
seed_everything(seed)
# init model parts
model = MODEL()
dl = model.train_dataloader()
optimizer = model.configure_optimizers()
# model to GPU
model = model.to(device)
epoch_losses = []
for epoch in range(num_epochs):
# run through full training set
for j, batch in enumerate(dl):
x, y = batch
x = x.cuda(0)
y = y.cuda(0)
batch = (x, y)
loss_dict = model.training_step(batch, j)
loss = loss_dict['loss']
loss.backward()
optimizer.step()
optimizer.zero_grad()
# track last epoch loss
epoch_losses.append(loss.item())
time_end = time.perf_counter()
times.append(time_end - time_start)
errors.append(epoch_losses[-1])
return errors, times
def lightning_loop(MODEL, num_runs=10, num_epochs=10):
errors = []
times = []
for i in range(num_runs):
time_start = time.perf_counter()
# set seed
seed = i
seed_everything(seed)
model = MODEL()
# init model parts
trainer = Trainer(
max_epochs=num_epochs,
progress_bar_refresh_rate=0,
weights_summary=None,
gpus=1,
early_stop_callback=False,
checkpoint_callback=False,
distributed_backend='dp',
deterministic=True,
)
trainer.fit(model)
final_loss = trainer.running_loss.last().item()
errors.append(final_loss)
time_end = time.perf_counter()
times.append(time_end - time_start)
return errors, times