Files
2026-07-13 13:35:51 +08:00

124 lines
3.7 KiB
Python

import time
import dgl
import dgl.nn as dglnn
import numpy as np
import torch
import torch.nn as nn
import torch.nn.functional as F
import torchmetrics.functional as MF
from ogb.nodeproppred import DglNodePropPredDataset
class SAGE(nn.Module):
def __init__(self, in_feats, n_hidden, n_classes):
super().__init__()
self.layers = nn.ModuleList()
self.layers.append(dglnn.SAGEConv(in_feats, n_hidden, "mean"))
self.layers.append(dglnn.SAGEConv(n_hidden, n_hidden, "mean"))
self.layers.append(dglnn.SAGEConv(n_hidden, n_classes, "mean"))
self.dropout = nn.Dropout(0.5)
def forward(self, sg, x):
h = x
for l, layer in enumerate(self.layers):
h = layer(sg, h)
if l != len(self.layers) - 1:
h = F.relu(h)
h = self.dropout(h)
return h
dataset = dgl.data.AsNodePredDataset(DglNodePropPredDataset("ogbn-products"))
graph = dataset[
0
] # already prepares ndata['label'/'train_mask'/'val_mask'/'test_mask']
model = SAGE(graph.ndata["feat"].shape[1], 256, dataset.num_classes).cuda()
opt = torch.optim.Adam(model.parameters(), lr=0.001, weight_decay=5e-4)
num_partitions = 1000
sampler = dgl.dataloading.ClusterGCNSampler(
graph,
num_partitions,
prefetch_ndata=["feat", "label", "train_mask", "val_mask", "test_mask"],
)
# DataLoader for generic dataloading with a graph, a set of indices (any indices, like
# partition IDs here), and a graph sampler.
dataloader = dgl.dataloading.DataLoader(
graph,
torch.arange(num_partitions).to("cuda"),
sampler,
device="cuda",
batch_size=100,
shuffle=True,
drop_last=False,
num_workers=0,
use_uva=True,
)
durations = []
for epoch in range(10):
t0 = time.time()
model.train()
for it, sg in enumerate(dataloader):
x = sg.ndata["feat"]
y = sg.ndata["label"]
m = sg.ndata["train_mask"].bool()
y_hat = model(sg, x)
loss = F.cross_entropy(y_hat[m], y[m])
opt.zero_grad()
loss.backward()
opt.step()
if it % 20 == 0:
acc = MF.accuracy(
y_hat[m],
y[m],
task="multiclass",
num_classes=dataset.num_classes,
)
mem = torch.cuda.max_memory_allocated() / 1000000
print("Loss", loss.item(), "Acc", acc.item(), "GPU Mem", mem, "MB")
tt = time.time() - t0
print("Run time for epoch# %d: %.2fs" % (epoch, tt))
durations.append(tt)
model.eval()
with torch.no_grad():
val_preds, test_preds = [], []
val_labels, test_labels = [], []
for it, sg in enumerate(dataloader):
x = sg.ndata["feat"]
y = sg.ndata["label"]
m_val = sg.ndata["val_mask"].bool()
m_test = sg.ndata["test_mask"].bool()
y_hat = model(sg, x)
val_preds.append(y_hat[m_val])
val_labels.append(y[m_val])
test_preds.append(y_hat[m_test])
test_labels.append(y[m_test])
val_preds = torch.cat(val_preds, 0)
val_labels = torch.cat(val_labels, 0)
test_preds = torch.cat(test_preds, 0)
test_labels = torch.cat(test_labels, 0)
val_acc = MF.accuracy(
val_preds,
val_labels,
task="multiclass",
num_classes=dataset.num_classes,
)
test_acc = MF.accuracy(
test_preds,
test_labels,
task="multiclass",
num_classes=dataset.num_classes,
)
print("Validation acc:", val_acc.item(), "Test acc:", test_acc.item())
print(
"Average run time for last %d epochs: %.2fs standard deviation: %.3f"
% ((epoch - 3), np.mean(durations[4:]), np.std(durations[4:]))
)