Diffusion offloader¶

The offloader owns component residency, transfer scheduling, memory accounting, prefetch, and teardown for diffusion execution.

Candidate invariants¶

OFFLOAD-INV-001: Residency is explicit¶

Rule: Each managed component MUST have one known residency state and one owner responsible for transitions.

OFFLOAD-INV-002: Use follows readiness¶

Rule: Runtime execution MUST NOT consume a component until its transfer to the required device is complete.

OFFLOAD-INV-003: Transfers preserve model state¶

Rule: Offloading MUST preserve parameter and buffer identity, dtype, device, and correctness required by the selected execution mode.

OFFLOAD-INV-004: Memory is bounded and released¶

Rule: Retained host and device copies MUST respect configured limits and provide deterministic teardown.

Allocator-cache retention MUST remain local to an explicit component owner, declare both cache and physical-free-memory bounds, release conservatively when telemetry is unavailable, and force release on failure or memory pressure. It MUST NOT replace unconditional executor shutdown cleanup.

Safe-change guide¶

Test enabled and disabled paths, repeated execution, asynchronous transfer, memory limits, failure, teardown, and numerical equivalence.