def test_join_running_workers_with_exception():
class ExpectedException(Exception):
pass
count = 0
def counter():
nonlocal count
time.sleep(0.1)
count += 1
return Batch((), 0)
with pytest.raises(ExpectedException):
with spawn_workers([fake_device() for _ in range(10)]) as (in_queues, out_queues):
def call_in_worker(i, f):
task = Task(CPUStream, compute=f, finalize=None)
in_queues[i].put(task)
for i in range(10):
call_in_worker(i, counter)
raise ExpectedException
# There's no nondeterminism because only 1 task can be placed in input
# queues.
assert count == 10
def test_grad_mode(grad_mode):
def detect_grad_enabled():
x = torch.rand(1, requires_grad=torch.is_grad_enabled())
return Batch(x, 0)
with torch.set_grad_enabled(grad_mode):
with spawn_workers([torch.device("cpu")]) as (in_queues, out_queues):
task = Task(CPUStream, compute=detect_grad_enabled, finalize=None)
in_queues[0].put(task)
ok, (_, batch) = out_queues[0].get()
assert ok
assert batch[0].requires_grad == grad_mode
def test_compute_exception():
"""Task.compute returns (False, exc_info) on failure."""
def zero_div():
0 / 0
with spawn_workers([torch.device("cpu")]) as (in_queues, out_queues):
t = Task(CPUStream, compute=zero_div, finalize=None)
in_queues[0].put(t)
ok, exc_info = out_queues[0].get()
assert not ok
assert isinstance(exc_info, tuple)
assert issubclass(exc_info[0], ZeroDivisionError)
def test_compute_success():
"""Task.compute returns (True, (task, batch)) on success."""
def _42():
return Batch(torch.tensor(42), 0)
with spawn_workers([torch.device("cpu")]) as (in_queues, out_queues):
t = Task(CPUStream, compute=_42, finalize=None)
in_queues[0].put(t)
ok, (task, batch) = out_queues[0].get()
assert ok
assert task is t
assert isinstance(batch, Batch)
assert batch[0].item() == 42
def test_worker_per_device():
cpu = torch.device("cpu")
cpu0 = torch.device("cpu", index=0)
fake1 = fake_device()
fake2 = fake_device()
with spawn_workers([cpu, cpu, cpu0, fake1, fake2]) as (in_queues, out_queues):
assert len(in_queues) == len(out_queues) == 5
# 0: cpu, 1: cpu, 2: cpu0
assert in_queues[0] is in_queues[1] is in_queues[2]
assert out_queues[0] is out_queues[1] is out_queues[2]
# 3: fake1, 4: fake2
assert in_queues[3] is not in_queues[4]
assert out_queues[3] is not out_queues[4]
def test_compute_multithreading():
"""Task.compute should be executed on multiple threads."""
thread_ids = set()
def log_thread_id():
thread_id = threading.current_thread().ident
thread_ids.add(thread_id)
return Batch((), 0)
with spawn_workers([fake_device() for _ in range(2)]) as (in_queues, out_queues):
for i in range(2):
t = Task(CPUStream, compute=log_thread_id, finalize=None)
in_queues[i].put(t)
for i in range(2):
out_queues[i].get()
assert len(thread_ids) == 2
def test_join_running_workers():
count = 0
def counter():
nonlocal count
time.sleep(0.1)
count += 1
return Batch((), 0)
with spawn_workers([fake_device() for _ in range(10)]) as (in_queues, out_queues):
def call_in_worker(i, f):
task = Task(CPUStream, compute=f, finalize=None)
in_queues[i].put(task)
for i in range(10):
call_in_worker(i, counter)
# There's no nondeterminism because 'spawn_workers' joins all running
# workers.
assert count == 10