Struct Window 

pub struct Window<'a, D: GraphDriver> { /* private fields */ }

A capture window on one stream: arming the pools before it opens, opening it, and instantiating what it recorded.

The three steps are ordered and the stream refuses them out of order (see StreamCapture); this type is where each one’s shared half lives.

Implementations

impl<'a, D: GraphDriver> Window<'a, D>

pub fn on(stream: &'a mut D::Stream) -> Self

The capture window on stream.

pub fn prepare(&mut self, stream_id: StreamId) -> Result<(), ServerError>

Arm the pools for a window about to open, before the warmup run.

Every allocation from here until the window closes is routed into the persistent pool, and which slices are already in use is snapshotted. The pool is warm by the time the window opens, so the run reuses those slices with no device allocation — which mid-capture is illegal. Instantiating pins everything the window added on the graph.

Both pools are armed: the device pool for tensor and kernel-info buffers, and the pinned host pool that stages each kernel’s info bytes to the device, where a fresh allocation mid-capture faults the same way.

Errors

The stream’s refusal, when it is not in a state a window can open from.

pub fn begin(&mut self) -> Result<(), ServerError>

Open the window: from here the driver records every launch issued on this stream until the window closes.

Errors

The driver’s refusal to begin recording, with the stream left as it was found — retention disarmed, allocation mode restored, capture state back to none — so the whole prepare-then-open sequence can be retried.

pub fn instantiate( &mut self, stream_id: StreamId, id: GraphId, ) -> Result<Graph<D>, Refused>

Close the window and instantiate what it recorded into a graph registered under id.

The window leaves capture mode first, so none of the paths below can wedge the stream in it — they re-enable the deferred fenced flushes and restore the allocation mode on the way out. A window the caller does not own is closed and torn down all the same, since nobody else is coming back to close it; only its owner gets a graph out of it.

Errors

Refused, which every failure here becomes — the driver’s refusal to close or instantiate, a recording an unreadable input left incomplete, an allocation inside the window, or no window at all. It carries the memory the caller now has to claim, empty when there was nothing to close.