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Last active December 3, 2020 13:22
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Testing/profiling webdataset data loading speed issue
from itertools import islice
from munch import Munch
import sys, os
from torch.utils.data import DataLoader
from torchvision import transforms
import time
import webdataset as wds
sys.path.append(os.getcwd())
num_iters = 50
args = Munch(input_size=224,
use_random_data=False,
shuffle_buffer=1,
batch_size=256,
num_workers=8,
tpu_cores=None)
url = "http://storage.googleapis.com/nvdata-openimages/openimages-train-{000000..000554}.tar"
url = f"pipe:curl -L -s {url} || true"
def identity(x):
return x
normalize = transforms.Normalize(
mean=[0.485, 0.456, 0.406],
std=[0.229, 0.224, 0.225])
preproc = transforms.Compose([
transforms.RandomResizedCrop(224),
transforms.RandomHorizontalFlip(),
transforms.ToTensor(),
normalize,
])
dataset = (
wds.Dataset(url)
.shuffle(100)
.decode("pil")
.to_tuple("jpg;png", "json")
.map_tuple(preproc, identity)
.batched(args.batch_size)
)
dataloader = DataLoader(dataset, num_workers=args.num_workers, batch_size=None)
start_time = time.time()
for i, sample in enumerate(islice(dataloader, 0, num_iters)):
print(f'\r{i}', end='')
print(f'\nend time={time.time() - start_time}')
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