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dmlc--dgl/tests/python/pytorch/utils/test_pin_memory.py
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2026-07-13 13:35:51 +08:00

97 lines
2.5 KiB
Python

import backend as F
import dgl
import pytest
import torch
@pytest.mark.skipif(
F._default_context_str == "cpu", reason="Need gpu for this test."
)
def test_pin_noncontiguous():
t = torch.empty([10, 100]).transpose(0, 1)
assert not t.is_contiguous()
assert not F.is_pinned(t)
with pytest.raises(dgl.DGLError):
dgl.utils.pin_memory_inplace(t)
@pytest.mark.skipif(
F._default_context_str == "cpu", reason="Need gpu for this test."
)
def test_pin_view():
t = torch.empty([100, 10])
v = t[10:20]
assert v.is_contiguous()
assert not F.is_pinned(t)
with pytest.raises(dgl.DGLError):
dgl.utils.pin_memory_inplace(v)
# make sure an empty view does not generate an error
u = t[10:10]
u = dgl.utils.pin_memory_inplace(u)
@pytest.mark.skipif(
F._default_context_str == "cpu", reason="Need gpu for this test."
)
def test_unpin_automatically():
# run a sufficient number of iterations such that the memory pool should be
# re-used
for j in range(10):
t = torch.ones(10000, 10)
assert not F.is_pinned(t)
nd = dgl.utils.pin_memory_inplace(t)
assert F.is_pinned(t)
del nd
# dgl.ndarray will unpin its data upon destruction
assert not F.is_pinned(t)
del t
@pytest.mark.skipif(
F._default_context_str == "cpu", reason="Need gpu for this test."
)
def test_pin_unpin_column():
g = dgl.graph(([1, 2, 3, 4], [0, 0, 0, 0]))
g.ndata["x"] = torch.randn(g.num_nodes())
g.pin_memory_()
assert g.is_pinned()
assert g.ndata["x"].is_pinned()
for col in g._node_frames[0].values():
assert col.pinned_by_dgl
assert col._data_nd is not None
g.ndata["x"] = torch.randn(g.num_nodes()) # unpin the old ndata['x']
assert g.is_pinned()
for col in g._node_frames[0].values():
assert not col.pinned_by_dgl
assert col._data_nd is None
assert not g.ndata["x"].is_pinned()
@pytest.mark.skipif(
F._default_context_str == "cpu", reason="Need gpu for this test."
)
def test_pin_empty():
t = torch.tensor([])
assert not t.is_pinned()
# Empty tensors will not be pinned or unpinned. It's a no-op.
# This is also the default behavior in PyTorch.
# We just check that it won't raise an error.
nd = dgl.utils.pin_memory_inplace(t)
assert not t.is_pinned()
if __name__ == "__main__":
test_pin_noncontiguous()
test_pin_view()
test_unpin_automatically()
test_pin_unpin_column()