Event#

classtorch.Event(device=None,*,enable_timing=False,blocking=False,interprocess=False)#

Query and record Stream status to identify or control dependencies across Stream and measure timing.

Parameters

• device (torch.device, optional) – the desired device for the Event.If not given, the currentaccelerator type will be used.

• enable_timing (bool,optional) – indicates if the event should measure time (default:False)

• blocking (bool,optional) – ifTrue,wait() will be blocking (default:False)

• interprocess (bool) – ifTrue, the event can be shared between processes (default:False)

Warning

Both blocking and interprocess are not supported right now and are noops.

Returns

An torch.Event object.

Return type

Event

Example:

>>>event=torch.Event()>>>e_cuda=torch.Event(device='cuda')

elapsed_time(end_event)→float#

Returns the elapsed time in milliseconds between when this event and theend_event areeach recorded viatorch.Stream.record_event().

Parameters

end_event (torch.Event) – The ending event has been recorded.

Returns

Time between starting and ending event in milliseconds.

Return type

float

Example:

>>>s_cuda=torch.Stream(device='cuda')>>>e1_cuda=s_cuda.record_event()>>>e2_cuda=s_cuda.record_event()>>>ms=e1_cuda.elapsed_time(e2_cuda)

query()→bool#

Check if the stream where this event was recorded already moved past the point where the event was recorded.Always returnsTrue if the Event was not recorded.

Returns

A boolean indicating if all work currently captured by event has completed.

Return type

bool

Example:

>>>s_cuda=torch.Stream(device='cuda')>>>e_cuda=s_cuda.record_event()>>>e_cuda.query()True

record(stream=None)→None#

Record the event in a given stream. The stream’s device must match the event’s device.This function is equivalent tostream.record_event(self).

Parameters

stream (torch.Stream, optional) – A stream to be recorded.If not given, the current stream will be used.

Example:

>>>e_cuda=torch.Event(device='cuda')>>>e_cuda.record()

synchronize()→None#

Wait for the event to complete. This prevents the CPU thread from proceeding until the event completes.

Example:

>>>s_cuda=torch.Stream(device='cuda')>>>e_cuda=s_cuda.record_event()>>>e_cuda.synchronize()

wait(stream=None)→None#

Make all future work submitted to the given stream wait for this event.

Parameters

stream (torch.Stream, optional) – A stream to synchronize.If not given, the current stream will be used.

Example:

>>>s1_cuda=torch.Stream(device='cuda')>>>s2_cuda=torch.Stream(device='cuda')>>>e_cuda=s1_cuda.record()>>>e_cuda.wait(s2)