Keep preparing the newest frame when both private owner lanes remain
referenced by a non-consuming timing client. Reuse only an unreferenced
completed buffer and continue serving eligible shared subscribers.
Track owner delivery separately from local retention so cadence advances
without acknowledging owner delivery or accepting phase feedback. Republish
the newest completed frame as soon as an owner lane becomes available.
Consume subscription notifications from the private owner queues. When
any lane gains a subscriber, request a retained-frame publication for
the current timing owner so a static desktop cannot leave it waiting.
Bump KVMFR to version 28 and attach generation, epoch, and deadline
identities to cadence deliveries and their timing records.
Accept phase corrections only for the exact completed publication. Keep
VM and client clocks independent by exchanging relative phase errors.
Make submission, completion, and work-estimate accounting best effort
so scheduler state cannot delay GPU submission or frame publication.
Replace the shared force and republish booleans with request tickets.
A completed publication now acknowledges only requests captured when it
began, so a concurrent immediate or cadence-break request survives.
Prepare each acquired content frame into one of two private GPU
candidates so the IddCx frame can be released without copying it to
IVSHMEM immediately.
Wake a high-resolution publisher at the client deadline and send the
newest completed candidate. Preserve accumulated damage across
superseded candidates, include the scheduling hold in end-to-end timing,
and keep transport work on the existing physical copy queue.
