Struct PpNRt 

pub struct PpNRt { /* private fields */ }

Implementations

impl PpNRt

pub fn get(e: &Engine) -> Result<&'static PpNRt, Box<dyn Error>>

The process-wide transport runtime, built on first use against the primary engine. The stage count + device map freeze at first build (one config per process — gates run one placement per invocation). Build errors are sticky and loud.

pub fn n_stages(&self) -> usize

pub fn cross_device(&self) -> bool

True iff any boundary crosses devices (transport = cudaMemcpyPeerAsync there).

pub fn engine<'a>(&'a self, s: usize, primary: &'a Engine) -> &'a Engine

The engine a stage’s subgraph must run through: the primary engine when the stage lives on the primary device, else the stage’s own (remote-context) engine.

pub fn enter(&self, s: usize) -> StreamOverride

Enter stage s: until the guard drops, every engine op on this thread launches on the stage’s stream (memra_runtime ambient-stream override).

pub fn tx( &self, b: usize, x: &CudaSlice<f32>, n: usize, ) -> Result<usize, Box<dyn Error>>

Boundary TX at boundary b (call within the stage-b scope; x = the materialized [n] residual): wait for the slot’s previous RX (write-after-read guard), copy x into the slot’s persistent buffer via the boundary’s transport on stage-b’s stream (the owning-stream/publication law), record ev_tx. Returns the slot index for the paired rx().

pub fn rx( &self, b: usize, slot_idx: usize, n: usize, ) -> Result<CudaSlice<f32>, Box<dyn Error>>

Boundary RX at boundary b (call within the stage-b+1 scope): wait on the slot’s ev_tx, copy the boundary buffer into a fresh working buffer (dtod on the RX stream — local on the RX device in both transports), record ev_rx. The returned buffer is RX-stage-owned: allocated, consumed, and eventually freed on that stage’s stream.

pub fn record_done(&self) -> Result<CudaEvent, Box<dyn Error>>

Deferred readback: record a fresh completion event on the LAST stage’s stream (call after the step’s logits matmul has been enqueued there).

pub fn readback_stream(&self) -> &Arc<CudaStream>

The dedicated readback stream (last stage’s context).