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

383 lines
12 KiB
Python

import argparse
import time
from functools import partial
import dgl
import dgl.nn.pytorch as dglnn
import numpy as np
import torch as th
import torch.nn as nn
import torch.nn.functional as F
import torch.optim as optim
import tqdm
from ogb.nodeproppred import DglNodePropPredDataset
from sampler import ClusterIter, subgraph_collate_fn
from torch.utils.data import DataLoader
class GAT(nn.Module):
def __init__(
self,
in_feats,
num_heads,
n_hidden,
n_classes,
n_layers,
activation,
dropout=0.0,
):
super().__init__()
self.n_layers = n_layers
self.n_hidden = n_hidden
self.n_classes = n_classes
self.layers = nn.ModuleList()
self.num_heads = num_heads
self.layers.append(
dglnn.GATConv(
in_feats,
n_hidden,
num_heads=num_heads,
feat_drop=dropout,
attn_drop=dropout,
activation=activation,
negative_slope=0.2,
)
)
for i in range(1, n_layers - 1):
self.layers.append(
dglnn.GATConv(
n_hidden * num_heads,
n_hidden,
num_heads=num_heads,
feat_drop=dropout,
attn_drop=dropout,
activation=activation,
negative_slope=0.2,
)
)
self.layers.append(
dglnn.GATConv(
n_hidden * num_heads,
n_classes,
num_heads=num_heads,
feat_drop=dropout,
attn_drop=dropout,
activation=None,
negative_slope=0.2,
)
)
def forward(self, g, x):
h = x
for l, conv in enumerate(self.layers):
h = conv(g, h)
if l < len(self.layers) - 1:
h = h.flatten(1)
h = h.mean(1)
return h.log_softmax(dim=-1)
def inference(self, g, x, batch_size, device):
"""
Inference with the GAT model on full neighbors (i.e. without neighbor sampling).
g : the entire graph.
x : the input of entire node set.
The inference code is written in a fashion that it could handle any number of nodes and
layers.
"""
num_heads = self.num_heads
for l, layer in enumerate(self.layers):
if l < self.n_layers - 1:
y = th.zeros(
g.num_nodes(),
self.n_hidden * num_heads
if l != len(self.layers) - 1
else self.n_classes,
)
else:
y = th.zeros(
g.num_nodes(),
self.n_hidden
if l != len(self.layers) - 1
else self.n_classes,
)
sampler = dgl.dataloading.MultiLayerFullNeighborSampler(1)
dataloader = dgl.dataloading.DataLoader(
g,
th.arange(g.num_nodes()),
sampler,
batch_size=batch_size,
shuffle=False,
drop_last=False,
num_workers=args.num_workers,
)
with dataloader.enable_cpu_affinity():
for input_nodes, output_nodes, blocks in tqdm.tqdm(dataloader):
block = blocks[0].int().to(device)
h = x[input_nodes].to(device)
if l < self.n_layers - 1:
h = layer(block, h).flatten(1)
else:
h = layer(block, h)
h = h.mean(1)
h = h.log_softmax(dim=-1)
y[output_nodes] = h.cpu()
x = y
return y
def compute_acc(pred, labels):
"""
Compute the accuracy of prediction given the labels.
"""
return (th.argmax(pred, dim=1) == labels).float().sum() / len(pred)
def evaluate(model, g, nfeat, labels, val_nid, test_nid, batch_size, device):
"""
Evaluate the model on the validation set specified by ``val_mask``.
g : The entire graph.
inputs : The features of all the nodes.
labels : The labels of all the nodes.
val_mask : A 0-1 mask indicating which nodes do we actually compute the accuracy for.
batch_size : Number of nodes to compute at the same time.
device : The GPU device to evaluate on.
"""
model.eval()
with th.no_grad():
pred = model.inference(g, nfeat, batch_size, device)
model.train()
labels_cpu = labels.to(th.device("cpu"))
return (
compute_acc(pred[val_nid], labels_cpu[val_nid]),
compute_acc(pred[test_nid], labels_cpu[test_nid]),
pred,
)
def model_param_summary(model):
"""Count the model parameters"""
cnt = sum(p.numel() for p in model.parameters() if p.requires_grad)
print("Total Params {}".format(cnt))
#### Entry point
def run(args, device, data, nfeat):
# Unpack data
(
train_nid,
val_nid,
test_nid,
in_feats,
labels,
n_classes,
g,
cluster_iterator,
) = data
labels = labels.to(device)
# Define model and optimizer
model = GAT(
in_feats,
args.num_heads,
args.num_hidden,
n_classes,
args.num_layers,
F.relu,
args.dropout,
)
model_param_summary(model)
model = model.to(device)
optimizer = optim.Adam(model.parameters(), lr=args.lr, weight_decay=args.wd)
# Training loop
avg = 0
best_eval_acc = 0
best_test_acc = 0
for epoch in range(args.num_epochs):
iter_load = 0
iter_far = 0
iter_back = 0
tic = time.time()
# Loop over the dataloader to sample the computation dependency graph as a list of
# blocks.
tic_start = time.time()
for step, cluster in enumerate(cluster_iterator):
mask = cluster.ndata.pop("train_mask")
if mask.sum() == 0:
continue
cluster.edata.pop(dgl.EID)
cluster = cluster.int().to(device)
input_nodes = cluster.ndata[dgl.NID]
batch_inputs = nfeat[input_nodes]
batch_labels = labels[input_nodes]
tic_step = time.time()
# Compute loss and prediction
batch_pred = model(cluster, batch_inputs)
batch_pred = batch_pred[mask]
batch_labels = batch_labels[mask]
loss = nn.functional.nll_loss(batch_pred, batch_labels)
optimizer.zero_grad()
tic_far = time.time()
loss.backward()
optimizer.step()
tic_back = time.time()
iter_load += tic_step - tic_start
iter_far += tic_far - tic_step
iter_back += tic_back - tic_far
if step % args.log_every == 0:
acc = compute_acc(batch_pred, batch_labels)
gpu_mem_alloc = (
th.cuda.max_memory_allocated() / 1000000
if th.cuda.is_available()
else 0
)
print(
"Epoch {:05d} | Step {:05d} | Loss {:.4f} | Train Acc {:.4f} | GPU {:.1f} MB".format(
epoch, step, loss.item(), acc.item(), gpu_mem_alloc
)
)
tic_start = time.time()
toc = time.time()
print(
"Epoch Time(s): {:.4f} Load {:.4f} Forward {:.4f} Backward {:.4f}".format(
toc - tic, iter_load, iter_far, iter_back
)
)
if epoch >= 5:
avg += toc - tic
if epoch % args.eval_every == 0 and epoch != 0:
eval_acc, test_acc, pred = evaluate(
model,
g,
nfeat,
labels,
val_nid,
test_nid,
args.val_batch_size,
device,
)
model = model.to(device)
if args.save_pred:
np.savetxt(
args.save_pred + "%02d" % epoch,
pred.argmax(1).cpu().numpy(),
"%d",
)
print("Eval Acc {:.4f}".format(eval_acc))
if eval_acc > best_eval_acc:
best_eval_acc = eval_acc
best_test_acc = test_acc
print(
"Best Eval Acc {:.4f} Test Acc {:.4f}".format(
best_eval_acc, best_test_acc
)
)
if epoch >= 5:
print("Avg epoch time: {}".format(avg / (epoch - 4)))
return best_test_acc.to(th.device("cpu"))
if __name__ == "__main__":
argparser = argparse.ArgumentParser("multi-gpu training")
argparser.add_argument(
"--gpu",
type=int,
default=0,
help="GPU device ID. Use -1 for CPU training",
)
argparser.add_argument("--num_epochs", type=int, default=20)
argparser.add_argument("--num_hidden", type=int, default=128)
argparser.add_argument("--num_layers", type=int, default=3)
argparser.add_argument("--num_heads", type=int, default=8)
argparser.add_argument("--batch_size", type=int, default=32)
argparser.add_argument("--val_batch_size", type=int, default=2000)
argparser.add_argument("--log_every", type=int, default=20)
argparser.add_argument("--eval_every", type=int, default=1)
argparser.add_argument("--lr", type=float, default=0.001)
argparser.add_argument("--dropout", type=float, default=0.5)
argparser.add_argument("--save_pred", type=str, default="")
argparser.add_argument("--wd", type=float, default=0)
argparser.add_argument("--num_partitions", type=int, default=15000)
argparser.add_argument("--num_workers", type=int, default=4)
argparser.add_argument(
"--data_cpu",
action="store_true",
help="By default the script puts all node features and labels "
"on GPU when using it to save time for data copy. This may "
"be undesired if they cannot fit in GPU memory at once. "
"This flag disables that.",
)
args = argparser.parse_args()
if args.gpu >= 0:
device = th.device("cuda:%d" % args.gpu)
else:
device = th.device("cpu")
# load ogbn-products data
data = DglNodePropPredDataset(name="ogbn-products")
splitted_idx = data.get_idx_split()
train_idx, val_idx, test_idx = (
splitted_idx["train"],
splitted_idx["valid"],
splitted_idx["test"],
)
graph, labels = data[0]
labels = labels[:, 0]
print("Total edges before adding self-loop {}".format(graph.num_edges()))
graph = dgl.remove_self_loop(graph)
graph = dgl.add_self_loop(graph)
print("Total edges after adding self-loop {}".format(graph.num_edges()))
num_nodes = train_idx.shape[0] + val_idx.shape[0] + test_idx.shape[0]
assert num_nodes == graph.num_nodes()
mask = th.zeros(num_nodes, dtype=th.bool)
mask[train_idx] = True
graph.ndata["train_mask"] = mask
graph.in_degrees(0)
graph.out_degrees(0)
graph.find_edges(0)
cluster_iter_data = ClusterIter(
"ogbn-products", graph, args.num_partitions, args.batch_size
)
cluster_iterator = DataLoader(
cluster_iter_data,
batch_size=args.batch_size,
shuffle=True,
pin_memory=True,
num_workers=args.num_workers,
collate_fn=partial(subgraph_collate_fn, graph),
)
in_feats = graph.ndata["feat"].shape[1]
n_classes = (labels.max() + 1).item()
# Pack data
data = (
train_idx,
val_idx,
test_idx,
in_feats,
labels,
n_classes,
graph,
cluster_iterator,
)
# Run 10 times
test_accs = []
nfeat = graph.ndata.pop("feat").to(device)
for i in range(10):
test_accs.append(run(args, device, data, nfeat))
print("Average test accuracy:", np.mean(test_accs), "±", np.std(test_accs))