Crate cobre_comm 

cobre-comm

Pluggable communication backend abstraction for the Cobre ecosystem.

This crate defines the Communicator and SharedMemoryProvider traits that decouple distributed computations from specific communication technologies. Backend implementations are feature-gated:

• local — single-process no-op (always available, zero overhead)
• mpi — MPI collectives via ferrompi
• tcp — TCP/IP coordinator pattern (no MPI required)
• shm — POSIX shared memory for single-node multi-process execution

The backend is selected at build time via Cargo feature flags, with optional runtime override through the COBRE_COMM_BACKEND environment variable.

Design principles

• Zero-cost static dispatch: generics over Communicator eliminate dynamic dispatch overhead on the hot path.
• Additive features: multiple backends can coexist in one binary.
• Orthogonal to the solver: algorithm crates depend on this crate for communication; it does not depend back.

Status

This crate is in early development. The API will change.

See the repository for the full roadmap.

Structs

HeapRegion

Shared memory region backed by a heap-allocated Vec<T>.

LocalBackend

Single-process communication backend with identity collective semantics.

Enums

BackendError

Errors that can occur during backend selection and initialization.

BackendKind

Programmatic backend selector for library-mode callers.

CommError

Errors that can occur during collective communication or shared memory operations.

ReduceOp

Element-wise reduction operations for allreduce.

Traits

CommData

Marker trait for types that can be transmitted through collective operations.

Communicator

Backend abstraction for collective communication operations.

LocalCommunicator

Object-safe sub-trait of Communicator for intra-node initialization coordination.

SharedMemoryProvider

Backend abstraction for intra-node shared memory region management.

SharedRegion

Handle to a shared memory region holding count elements of type T.

Functions

available_backends

Returns all backend names compiled into this binary.

create_communicator

Construct the active communication backend (no-feature build).